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All 23 posts Subject: Henry condensation yield. Please login to post Down

wolfx
(Hive Bee)
10-06-04 06:06
No 534644
User Picture       Henry condensation yield.

SWIW has just finished his first Henry condensation, used 50 g 2,5-DMBA, procedure almost exactly like Pihkal # 20. After dissolving in IPA, filtering, washing the filter cake with IPA, repeat till filtrate not dark, got aproximately 65 g of a nice, homogeneous carrot colored substance, nice color, needles seen but kind of amorphous look. Still a bit wet with IPA.

My problem, the yield is close or higher than 100 %. Obviously there are impurities and/or IPA mixed in. My question, can I input this as it is for reduction ?

According to Shulgin, what he got was of sufficient purity to input to the reduction step. I am just hoping the impurities are not going to affect the reduction yield. Of course, I am sure Shulgin got better product than I did, but am just hoping impurities might not adversely affect reduction step yield, at least not too much. I hope to have enough to distill the 2C-H ( and hopefully the 2C-B also ).

Also, what would be a typical yield for the Henry condensation would be ?

Worth re-xtalizing this from IPA ? Or use as it is OK ?

Just in case, 2,5-DMBA 98 % pure; nitro from RC fuel; ammonium acetate reagent grade.

I am still overloaded with work, but hope to find time to try to reduce this to 2C-H, maybe next week.

Rhodium
(Chief Bee)
10-06-04 15:31
No 534682
User Picture       nitrostyrene yields

You need to dry the nitrostyrene to a crisp first, especially if you are going for a hydride-based reduction. Check https://www.rhodium.ws/chemistry/2cb.synthesis.html for an overview of typical yields using various catalysts.

^{The Hive - Clandestine Chemists Without Borders}

wolfx
(Hive Bee)
10-06-04 20:25
No 534726
User Picture       Thanks Rhodium. No, I am not planning to use...

Thanks Rhodium. No, I am not planning to use LAH or something like that. Will tell you what happened later. Will try to dry it, still too clumpy and wet.

wolfx
(Hive Bee)
10-07-04 18:40
No 534848
User Picture       Revised yield.

After drying, now nitrostyrene looks dry, powdery, IPA smell almost totally gone, weight went down to 39.6 g. This corresponds to 62 % yield, a bit less I guess.

wolfx
(Hive Bee)
10-14-04 14:07
No 535812
User Picture       Follow up.

SWIW has reduced 19 g of the above nitrostyrene with zinc dust 5:1 by weight, with good results. Got 13.1 g of a white powdery substance, just slightly yellow, hopefully 2C-H.HCl. Will try to brominate later on. Still want to reduce the remaining nitrostyrene first.

icexool
(Newbee)
10-14-04 19:16
No 535854
      Where did you substitute the LAH for?

Where did you substitute the LAH for?
And did you mean 5:1 Zn didn't you use Zn+MeOH.

indole_amine
(Hive Bee)
10-14-04 20:02
No 535859
User Picture       Zn instead of LAH

With nitroethenes, Zn/HCl substitutes for LAH... tongue

(it reduces both the C=C bond and the nitro group, but doesn't work with longer alkyl chains like nitropropenes)

(edit: Yes, what you did is the Leminger reduction... but Zn/NH4Cl can reduce oximes - a modification of the Zn/formic reduction posted by Lego (Post 477266 (Lego: "Reduction of oximes with zinc/ammonium formate", Novel Discourse)) I just got confused as there is currently a thread in the novel discourse dealing with Zn reductions, too... (Post 535551 (pablos: "Oxime", Novel Discourse) ), and besides, Zn/HCOOH also reduces nitro groups.. sorry.)

_{indole_amine}

wolfx
(Hive Bee)
10-15-04 01:45
No 535900
User Picture       Leminger

As far as I know, the reducing agent is Zn dust only. Look in the Rhodium site, there is one paper under 2C-B, the autor is Leminger. I used MeOH as the solvent with some HCl excess. Temperature control under 30 C only OK. Got this from The Hive, private communication.

Worst part is the work up, but OK if done correctly. I cloggeg my sep funnel with Zn(OH)2, then decided to extract with toluene + big plastic container + stirrer, worked fine.

So far looks OK, clean, I will know for sure if bromination works as expected.

indole_amine
(Hive Bee)
10-15-04 05:29
No 535913
User Picture       or maybe..

BTW you could also reduce the nitrostyrene to the nitroethane with NaBH4 (that is, if you have some), and then to the phenethylamine with Zn/NH4COOH - 2 steps vs. one, but maybe with more ease (and maybe higher yields?).

Usually the results are better if two reductions are done with two different reactions; but in this case Leminger is almost perfect.

_{indole_amine}

wolfx
(Hive Bee)
10-15-04 14:20
No 535970
User Picture       Worth it ?

I have asked someone here about doing it with two reductions or one, I was advised to do it with one reduction. BTW, my yield is already 65 % ( coarse crystallization, not distilled yet ) and to beat that you would need something like 90 % followed by 75 % or so.

For instance, if you have say 0.9 * 0.7 = 0.63 it is less than 0.65.

Also, like to hear you say Leminger it is almost perfect for this reduction. I think it is very clean, no tar, final product looks like it has been gassed out.

Also, modifications to paper procedure include maximum temperature 30 C and also to add all nitrostyrene after the MeOH and HCl, then add the Zn in small portions.

I will tell you whatever happened later.

amine
(Hive Bee)
10-15-04 21:14
No 536001
      Zn/HCl method.

Hey, can you please post your proceedure for the reduction of the nitrostryene, swim has had aweful results when attempting it.

Saddam_Hussein
(Hive Bee)
10-15-04 21:42
No 536004
User Picture       temp

Keep your temperature under control at all times. Ice bath is good idea.

President of the Iraqi Chemical Weapons of Mass Destruction Development Society

wolfx
(Hive Bee)
10-16-04 03:14
No 536035
User Picture       Reduction with Zinc Dust / Al ( by Wolfx )

Dear Amine, and others, there it is. I have not contacted the person who gave me the hints on this, but I assume he would not object. If he agrees, I will of course include his name later on. One word of caution, this still not finished, but, I have this fellow word it works, I have seen the amine on top, fishy smell, got it after the A/B, etc, looks right.

Reduction with Zinc Dust / Al ( by Wolfx )

   - Setup:

   - Place a 2 l BF over a stirrer, with a fitting funnel on top and
   also a thermometer. Don't let the thermometer to hit the spin-
   ning bar. Cool the BF with ice. During the zinc addition and
   after, do not let temperature to exceed 30 C.

   Reagents :

   - 2,5-dimethoxynitrostyrene ( 20 g )
   - Zinc dust ( 100 g )
   - MeOH ( 200 ml )
   - HCl 31 % ( 300 ml )

   Procedure :

   - Add 200 ml MeOH to the BF. Slowly add 300 ml 31 % HCl. Watch the
   temperature, let it cool down to under 30 C.

   - Add all of the 2,5-dimethoxynitrostyrene all at once. It should
   dissolve easily, everything then a nice uniform orange color.

   - Start dropping in the zinc dust in small ammounts. It will foam
   a bit, but soon stops, foaming decreases. Watch the temperature
   at every zinc dust addition. Don't let it go over 30 C. Should
   take one hour or more.

   - After addition complete, drip inside BF a small ammount of MeOH
   to wash orange foamed in sides of BF. Glass will look clear now.

   - Stir for a total reaction time of 7 h, including zinc addition.
   At the end, the orange color is completely gone, there is a clear
   watery liquid with some zinc at the bottom. Color yellow-gray,
   clear, transparent.

   - Filter out zinc. Should now have some 700 ml of a clear yellow
   liquid, looks like white wine.

   - Workup :

   - Setup for distillation, distill out HCl and most of the MeOH.

   - Dissolve 200 g NaOH in 600 ml water. It will heat up, let it cool
   down to RT or close.

   - With cooling, stirring, slowly drip in the filtrate in small
   increments. Newly formed Zn(OH)2 will make solution thick milk
   white. Keep stirring.

   - After all filtrate added in, add some 150 ml of toluene and stir
   for a few minutes. Place in fridge ( optional ) and wait one hour
   or so. Now, most of the Zn(OH)2 on bottom. Carefully decant the
   top water + toluene layer. Filter out any Zn(OH)2 carried over.

   - Separate the toluene, it will be on top of the water layer. Wash
   the toluene if you feel like.

   - Now, gas it or back extract with dilute HCl and dry on low heat.

   - Should have now 2C-H.HCl.

   - Comments :

   - This is a modification of the Leminger reduction, hints on the
   reduction procedure and workup given to me as private com-
   munication.

   - Previous post has been edited. Changed title, added reagent ammounts, also added distilling out HCl + MeOH before dripping in NaOH. Have not tried workup whithout distilling out the HCl + MeOH first, but it should work, I think there is NaOH enough. In the original Leminger paper it is not done.

starlight
(Hive Bee)
10-16-04 06:04
No 536050
      are you sure?

BTW you could also reduce the nitrostyrene to the nitroethane with NaBH4 (that is, if you have some), and then to the phenethylamine with Zn/NH4COOH - 2 steps vs. one, but maybe with more ease (and maybe higher yields?).

Is this from personal experience or are you theorizing? In my experience, Zn/formate reductions of nitroalkanes work but it's tricky to get good yields on a consistent basis. Other methods have been found to perform better.

Tricky
(Stunning)
10-16-04 06:50
No 536053
      Al instead of Zn!!!

Why don't you wanna try Al instead of all pain in the butt, you're have with other Reductians???
Original procedure: https://www.rhodium.ws/chemistry/nitrostyrene.reduction.alhg.html
Everything works very well.
Good luck.

-who dares, wins-

wolfx
(Hive Bee)
10-16-04 13:55
No 536083
User Picture       Post edited.

The original one has been edited, but no major changes.
Added removing HCl + MeOH before dripping in NaOH solution.

Answering to Tricky, never tried the Al reduction, but this is nice and easy to do, the worst part is the Zn(OH)2 but easy to deal with. I have been told you can get 75 % yield.

indole_amine
(Hive Bee)
10-16-04 17:15
No 536095
User Picture       no personal experience, but others have...

Starlight:

There are threads about experiences with Zn/NH4COOH, one I remember is by SpicyBrown: it is about 4-fluoroamphetamine and has the words "full report" in its title (or at least something similar tongue ). If you search for SBs posts, you will find it very quickly...

_{indole_amine}

starlight
(Hive Bee)
10-18-04 18:30
No 536395
      I know some have had success

I'm aware of the thread you are talking about (I've read most of the posts here over the last four or five years), but others (including very experienced bees) have experienced inconsistent yields using the Zn/NH4COOH method.

indole_amine
10-19-04 12:55
      good to know
(Rated as: redundant)

Vaaguh
(Hive Bee)
10-19-04 13:23
No 536589
User Picture       tricky indeed

The nitro reduction using Zn/HCOOH or Zn/NH4COOH is indeed and unofortunateley very inconsistent.

Has anyone tried to freebase the lemminger post reaction with aq NH3? This might improve the ease of workup.

Hippler

wolfx
(Hive Bee)
10-30-04 16:24
No 538747
User Picture       2C-H distillation

SWIW distilled 2C-H sucessfully. Some details :

Short path used; Oil bath temperature initial 160 C, final 195 C. This with good vacuum, initial 0.8 mm Hg, final 3.3 mm Hg. Good one, very little vacuum degradation.

After distillation, with glassware disassembled : Noticed white carbonate xtals first just at tip of condenser. In one hour or so, the 2C-H droplets inside had become white carbonate xtals.

Distilled almost to the last drop, just a small pool of brown oil left. I hope this means very little dimeric impurity.

Yield 80 %, 20 g 2C-H.HCl from almost 25 g yellow, crude 2C-H.HCl.

One more : Tried to xtalize from IPA/ acetone, a mess. The acetone dissolved the incipient xtals instead of crashing out. After drying on hot plate, low heat ( it was taking forever to dry the IPA ) and much scrubbing and stirring with spoon in shallow pyrex dish, then got circa 20 g of powdery, a bit sticky, snow white 2C-H.HCl.

Need one week or two break, then will try to brominate one gram. If OK, will brominate more.

Vaaguh
(Hive Bee)
11-01-04 11:36
No 539062
User Picture       distilling

Did you distill directly from the post freebase mixture or did you distill the residual oil from the extracts?

Hippler

wolfx
(Hive Bee)
11-01-04 15:23
No 539085
      Distillation detail

I first got almost 25 g crude 2C-H, see procedure posted. First added water to toluene, then HCl dropwise, checking pH with electronic meter till acidic, not bouncing back to high pH. Next, dried water in low heat ( hotplate, low setting, could touch it with bare hands ). This after the reduction, means how I got the crude 2C-H.HCl. See procedure posted before.

The crude 2C-H.HCl as above was dissolved in aprox. 50 ml water. Added some 20 ml water with 5 g NaOH dissolved in, in sep. funnel, shake real hard. Freebase separated easily, clear, transparent yellow oil on bottom. Aded a bit DCM, shake. Separated it out.

Added a bit more NaOH to remaining water, also some more DCM, this time got some emulsion in DCM layer. Emulsion broken easily by letting it run through sep. funnel hole. Poured it back into sep. funnel, this time separated a bit of scum impurity on top of DCM.

Combined with first extraction, started distillation with no vacuum. DCM difficult to come out, started distilling with aspirator soon. Finnaly rest of DCM came out. Switched receiving BF with a clean one. Most of DCM just evaporated out, almost nothing on receiving flask.

Kept distilling with aspirator till oil started showing up, oil bath at 105 C or so, then switched to vacuum pump.

The oil still had to go all the way to 160 C when finnaly the 2C-H slowly climbed up the condenser and started dropping in receiving flask.

Do not try IPA/acetone here, gas it in toluene.

If you have ethyl ether then IPA way should be OK, or just dry from water, low heat ( after neutralizing dropwise with HCl, of course ). Might be difficult to xtalize this way.

The IPA acetone works fine with MDMA, but looks like it does not work well with 2C-H.

Good luck.

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	All 23 posts		Subject: Henry condensation yield.		Please login to post		Down


		wolfx (Hive Bee) 10-06-04 06:06 No 534644				Henry condensation yield.
						SWIW has just finished his first Henry condensation, used 50 g 2,5-DMBA, procedure almost exactly like Pihkal # 20. After dissolving in IPA, filtering, washing the filter cake with IPA, repeat till filtrate not dark, got aproximately 65 g of a nice, homogeneous carrot colored substance, nice color, needles seen but kind of amorphous look. Still a bit wet with IPA. My problem, the yield is close or higher than 100 %. Obviously there are impurities and/or IPA mixed in. My question, can I input this as it is for reduction ? According to Shulgin, what he got was of sufficient purity to input to the reduction step. I am just hoping the impurities are not going to affect the reduction yield. Of course, I am sure Shulgin got better product than I did, but am just hoping impurities might not adversely affect reduction step yield, at least not too much. I hope to have enough to distill the 2C-H ( and hopefully the 2C-B also ). Also, what would be a typical yield for the Henry condensation would be ? Worth re-xtalizing this from IPA ? Or use as it is OK ? Just in case, 2,5-DMBA 98 % pure; nitro from RC fuel; ammonium acetate reagent grade. I am still overloaded with work, but hope to find time to try to reduce this to 2C-H, maybe next week.



		Rhodium (Chief Bee) 10-06-04 15:31 No 534682				nitrostyrene yields
						You need to dry the nitrostyrene to a crisp first, especially if you are going for a hydride-based reduction. Check https://www.rhodium.ws/chemistry/2cb.synthesis.html for an overview of typical yields using various catalysts. ^{The Hive - Clandestine Chemists Without Borders}



		wolfx (Hive Bee) 10-06-04 20:25 No 534726				Thanks Rhodium. No, I am not planning to use...
						Thanks Rhodium. No, I am not planning to use LAH or something like that. Will tell you what happened later. Will try to dry it, still too clumpy and wet.



		wolfx (Hive Bee) 10-07-04 18:40 No 534848				Revised yield.
						After drying, now nitrostyrene looks dry, powdery, IPA smell almost totally gone, weight went down to 39.6 g. This corresponds to 62 % yield, a bit less I guess.



		wolfx (Hive Bee) 10-14-04 14:07 No 535812				Follow up.
						SWIW has reduced 19 g of the above nitrostyrene with zinc dust 5:1 by weight, with good results. Got 13.1 g of a white powdery substance, just slightly yellow, hopefully 2C-H.HCl. Will try to brominate later on. Still want to reduce the remaining nitrostyrene first.



		icexool (Newbee) 10-14-04 19:16 No 535854				Where did you substitute the LAH for?
						Where did you substitute the LAH for? And did you mean 5:1 Zn didn't you use Zn+MeOH.



		indole_amine (Hive Bee) 10-14-04 20:02 No 535859				Zn instead of LAH
						With nitroethenes, Zn/HCl substitutes for LAH... (it reduces both the C=C bond and the nitro group, but doesn't work with longer alkyl chains like nitropropenes) (edit: Yes, what you did is the Leminger reduction... but Zn/NH4Cl can reduce oximes - a modification of the Zn/formic reduction posted by Lego (Post 477266 (Lego: "Reduction of oximes with zinc/ammonium formate", Novel Discourse)) I just got confused as there is currently a thread in the novel discourse dealing with Zn reductions, too... (Post 535551 (pablos: "Oxime", Novel Discourse) ), and besides, Zn/HCOOH also reduces nitro groups.. sorry.) _{indole_amine}



		wolfx (Hive Bee) 10-15-04 01:45 No 535900				Leminger
						As far as I know, the reducing agent is Zn dust only. Look in the Rhodium site, there is one paper under 2C-B, the autor is Leminger. I used MeOH as the solvent with some HCl excess. Temperature control under 30 C only OK. Got this from The Hive, private communication. Worst part is the work up, but OK if done correctly. I cloggeg my sep funnel with Zn(OH)2, then decided to extract with toluene + big plastic container + stirrer, worked fine. So far looks OK, clean, I will know for sure if bromination works as expected.



		indole_amine (Hive Bee) 10-15-04 05:29 No 535913				or maybe..
						BTW you could also reduce the nitrostyrene to the nitroethane with NaBH4 (that is, if you have some), and then to the phenethylamine with Zn/NH4COOH - 2 steps vs. one, but maybe with more ease (and maybe higher yields?). Usually the results are better if two reductions are done with two different reactions; but in this case Leminger is almost perfect. _{indole_amine}



		wolfx (Hive Bee) 10-15-04 14:20 No 535970				Worth it ?
						I have asked someone here about doing it with two reductions or one, I was advised to do it with one reduction. BTW, my yield is already 65 % ( coarse crystallization, not distilled yet ) and to beat that you would need something like 90 % followed by 75 % or so. For instance, if you have say 0.9 * 0.7 = 0.63 it is less than 0.65. Also, like to hear you say Leminger it is almost perfect for this reduction. I think it is very clean, no tar, final product looks like it has been gassed out. Also, modifications to paper procedure include maximum temperature 30 C and also to add all nitrostyrene after the MeOH and HCl, then add the Zn in small portions. I will tell you whatever happened later.



		amine (Hive Bee) 10-15-04 21:14 No 536001				Zn/HCl method.
						Hey, can you please post your proceedure for the reduction of the nitrostryene, swim has had aweful results when attempting it.



		Saddam_Hussein (Hive Bee) 10-15-04 21:42 No 536004				temp
						Keep your temperature under control at all times. Ice bath is good idea. President of the Iraqi Chemical Weapons of Mass Destruction Development Society



		wolfx (Hive Bee) 10-16-04 03:14 No 536035				Reduction with Zinc Dust / Al ( by Wolfx )
						Dear Amine, and others, there it is. I have not contacted the person who gave me the hints on this, but I assume he would not object. If he agrees, I will of course include his name later on. One word of caution, this still not finished, but, I have this fellow word it works, I have seen the amine on top, fishy smell, got it after the A/B, etc, looks right. Reduction with Zinc Dust / Al ( by Wolfx ) - Setup: - Place a 2 l BF over a stirrer, with a fitting funnel on top and also a thermometer. Don't let the thermometer to hit the spin- ning bar. Cool the BF with ice. During the zinc addition and after, do not let temperature to exceed 30 C. Reagents : - 2,5-dimethoxynitrostyrene ( 20 g ) - Zinc dust ( 100 g ) - MeOH ( 200 ml ) - HCl 31 % ( 300 ml ) Procedure : - Add 200 ml MeOH to the BF. Slowly add 300 ml 31 % HCl. Watch the temperature, let it cool down to under 30 C. - Add all of the 2,5-dimethoxynitrostyrene all at once. It should dissolve easily, everything then a nice uniform orange color. - Start dropping in the zinc dust in small ammounts. It will foam a bit, but soon stops, foaming decreases. Watch the temperature at every zinc dust addition. Don't let it go over 30 C. Should take one hour or more. - After addition complete, drip inside BF a small ammount of MeOH to wash orange foamed in sides of BF. Glass will look clear now. - Stir for a total reaction time of 7 h, including zinc addition. At the end, the orange color is completely gone, there is a clear watery liquid with some zinc at the bottom. Color yellow-gray, clear, transparent. - Filter out zinc. Should now have some 700 ml of a clear yellow liquid, looks like white wine. - Workup : - Setup for distillation, distill out HCl and most of the MeOH. - Dissolve 200 g NaOH in 600 ml water. It will heat up, let it cool down to RT or close. - With cooling, stirring, slowly drip in the filtrate in small increments. Newly formed Zn(OH)2 will make solution thick milk white. Keep stirring. - After all filtrate added in, add some 150 ml of toluene and stir for a few minutes. Place in fridge ( optional ) and wait one hour or so. Now, most of the Zn(OH)2 on bottom. Carefully decant the top water + toluene layer. Filter out any Zn(OH)2 carried over. - Separate the toluene, it will be on top of the water layer. Wash the toluene if you feel like. - Now, gas it or back extract with dilute HCl and dry on low heat. - Should have now 2C-H.HCl. - Comments : - This is a modification of the Leminger reduction, hints on the reduction procedure and workup given to me as private com- munication. - Previous post has been edited. Changed title, added reagent ammounts, also added distilling out HCl + MeOH before dripping in NaOH. Have not tried workup whithout distilling out the HCl + MeOH first, but it should work, I think there is NaOH enough. In the original Leminger paper it is not done.



		starlight (Hive Bee) 10-16-04 06:04 No 536050				are you sure?
						BTW you could also reduce the nitrostyrene to the nitroethane with NaBH4 (that is, if you have some), and then to the phenethylamine with Zn/NH4COOH - 2 steps vs. one, but maybe with more ease (and maybe higher yields?). Is this from personal experience or are you theorizing? In my experience, Zn/formate reductions of nitroalkanes work but it's tricky to get good yields on a consistent basis. Other methods have been found to perform better.



		Tricky (Stunning) 10-16-04 06:50 No 536053				Al instead of Zn!!!
						Why don't you wanna try Al instead of all pain in the butt, you're have with other Reductians??? Original procedure: https://www.rhodium.ws/chemistry/nitrostyrene.reduction.alhg.html Everything works very well. Good luck. -who dares, wins-



		wolfx (Hive Bee) 10-16-04 13:55 No 536083				Post edited.
						The original one has been edited, but no major changes. Added removing HCl + MeOH before dripping in NaOH solution. Answering to Tricky, never tried the Al reduction, but this is nice and easy to do, the worst part is the Zn(OH)2 but easy to deal with. I have been told you can get 75 % yield.



		indole_amine (Hive Bee) 10-16-04 17:15 No 536095				no personal experience, but others have...
						Starlight: There are threads about experiences with Zn/NH4COOH, one I remember is by SpicyBrown: it is about 4-fluoroamphetamine and has the words "full report" in its title (or at least something similar ). If you search for SBs posts, you will find it very quickly... _{indole_amine}



		starlight (Hive Bee) 10-18-04 18:30 No 536395				I know some have had success
						I'm aware of the thread you are talking about (I've read most of the posts here over the last four or five years), but others (including very experienced bees) have experienced inconsistent yields using the Zn/NH4COOH method.



		indole_amine 10-19-04 12:55				good to know (Rated as: redundant)



		Vaaguh (Hive Bee) 10-19-04 13:23 No 536589				tricky indeed
						The nitro reduction using Zn/HCOOH or Zn/NH4COOH is indeed and unofortunateley very inconsistent. Has anyone tried to freebase the lemminger post reaction with aq NH3? This might improve the ease of workup. Hippler



		wolfx (Hive Bee) 10-30-04 16:24 No 538747				2C-H distillation
						SWIW distilled 2C-H sucessfully. Some details : Short path used; Oil bath temperature initial 160 C, final 195 C. This with good vacuum, initial 0.8 mm Hg, final 3.3 mm Hg. Good one, very little vacuum degradation. After distillation, with glassware disassembled : Noticed white carbonate xtals first just at tip of condenser. In one hour or so, the 2C-H droplets inside had become white carbonate xtals. Distilled almost to the last drop, just a small pool of brown oil left. I hope this means very little dimeric impurity. Yield 80 %, 20 g 2C-H.HCl from almost 25 g yellow, crude 2C-H.HCl. One more : Tried to xtalize from IPA/ acetone, a mess. The acetone dissolved the incipient xtals instead of crashing out. After drying on hot plate, low heat ( it was taking forever to dry the IPA ) and much scrubbing and stirring with spoon in shallow pyrex dish, then got circa 20 g of powdery, a bit sticky, snow white 2C-H.HCl. Need one week or two break, then will try to brominate one gram. If OK, will brominate more.



		Vaaguh (Hive Bee) 11-01-04 11:36 No 539062				distilling
						Did you distill directly from the post freebase mixture or did you distill the residual oil from the extracts? Hippler



		wolfx (Hive Bee) 11-01-04 15:23 No 539085				Distillation detail
						I first got almost 25 g crude 2C-H, see procedure posted. First added water to toluene, then HCl dropwise, checking pH with electronic meter till acidic, not bouncing back to high pH. Next, dried water in low heat ( hotplate, low setting, could touch it with bare hands ). This after the reduction, means how I got the crude 2C-H.HCl. See procedure posted before. The crude 2C-H.HCl as above was dissolved in aprox. 50 ml water. Added some 20 ml water with 5 g NaOH dissolved in, in sep. funnel, shake real hard. Freebase separated easily, clear, transparent yellow oil on bottom. Aded a bit DCM, shake. Separated it out. Added a bit more NaOH to remaining water, also some more DCM, this time got some emulsion in DCM layer. Emulsion broken easily by letting it run through sep. funnel hole. Poured it back into sep. funnel, this time separated a bit of scum impurity on top of DCM. Combined with first extraction, started distillation with no vacuum. DCM difficult to come out, started distilling with aspirator soon. Finnaly rest of DCM came out. Switched receiving BF with a clean one. Most of DCM just evaporated out, almost nothing on receiving flask. Kept distilling with aspirator till oil started showing up, oil bath at 105 C or so, then switched to vacuum pump. The oil still had to go all the way to 160 C when finnaly the 2C-H slowly climbed up the condenser and started dropping in receiving flask. Do not try IPA/acetone here, gas it in toluene. If you have ethyl ether then IPA way should be OK, or just dry from water, low heat ( after neutralizing dropwise with HCl, of course ). Might be difficult to xtalize this way. The IPA acetone works fine with MDMA, but looks like it does not work well with 2C-H. Good luck.

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