Bwiti (Hive Addict)
10-25-01 00:36
No 228619
      Piperonyl Chloride Question  Bookmark   

  What does a bee have to suck to find a patent specifically geared towards the production of piperonyl chloride? Would the chloromethylation of 1,3-benzodioxole with ZnCl and HCl gas give about the same yield of chloride as one would get with benzene? Can any synth for the production of benzyl chloride be tweaked to make piperonyl chloride? Thanks!cool

  The christian god hates your soul. Care for a little necrophilia?
 
 
 
 
    Rhodium
(Chief Bee)
10-25-01 02:35
No 228633
      Re: Piperonyl Chloride Question  Bookmark   

The reaction will work, but the yields will be somewhat lower I think, because the methylenedioxy ring is moderately sensitive to acids. Some of the isomeric ortho-chloromethyl compound will also be formed.
 
 
 
 
    foxy2
(Distinctive Doe)
10-25-01 10:09
No 228725
      Re: Piperonyl Chloride Question  Bookmark   

This might bee what you want smile

Chloromethylation of 1,3-benzodioxole in the presence of micellar catalysts.  
Yingyong Huaxue  (2000),  17(5),  563-565. 
CODEN: YIHUED  ISSN: 1000-0518.  Journal  written in Chinese.

Abstract
1,3-Benzodioxole was monochloromethylated directly by aq. formaldehyde and hydrogen chloride gas in CCl4 in the presence of quaternary ammonium salts: c16H33(CH3)3NX (X = Br, Cl), C12H25(CH3)3NCl, C12H25(CH3)2(C6H5CH2)NCl and (C4H9)4NBr.  With hexadecyltrimethylammonium bromide at temp. 60-65 for 15 h of reaction, 1,3-benzodioxole was converted to piperonyl chloride with conversion >98% and selectivity up to 97%.  The method has advantages of high selectivity, high conversion, negligible byproducts and easy workup of the mail product.


a,a-Dimethyl-3,4-methylenedioxyhydrocinnamic aldehyde and flavoring materials containing the compound.
Sotoguchi, Tsukasa; Yamamoto, Takeshi.  (Takasago Perfumery Co., Ltd., Japan).    Jpn. Kokai Tokkyo Koho  (1989),     8 pp.  CODEN: JKXXAF  JP  01022868  A2  19890125  Heisei.
Patent  written in Japanese.

Abstract
Flavoring materials contain the title compd. (I).  I, which has strong and continuous floral fragrance, is stable and useful for various uses, e. g. cosmetics, hair prepns., soaps, detergents, drugs, etc.  Treatment of 366 g methylenedioxybenzene with 99 g paraformaldehyde in MePh with feeding HCl at 25-35 for 4 h gave 423.6 g crude 3,4-methylenedioxybenzyl chloride, which was treated with 173 g isobutyraldehyde in the presence of NaOH and Bu4NI in H2O-MePh at 65 for 7 h to afford 481 g crude I.  Pure I (212 g) was obtained after distn.  A white soap flavored with 1% I was stored in a sealed container at 50 for 30 days to show no change of the flavor or discoloration of the soap, whereas change of flavor and yellowish discoloration were obsd. when a-methyl-3,4-methylenedioxyhydrocinnamic aldehyde was used instead of I. 
 

Do Your Part To Win The War
 
 
 
 
    Bwiti
(Hive Addict)
10-25-01 17:44
No 228834
      Re: Piperonyl Chloride Question  Bookmark   

  Thanks! That is exactly what I was looking for. Making a quaternary ammonium salt won't be a hard task, because there are several patents that will show me the way. This is a good thing, because who wants to go through the trouble of brominating their 1,3,-benzodioxole, putting it through a Grignard, reacting with allylbromide, etc., when all one needs is hexamine and the chloride, and making product from a benzaldehyde is easy. It's not as easy as making tweak from safrole-azide, but sassy oil is getting harder to find. Thanks again and peace!cool

  The christian god hates your soul. Care for a little necrophilia?
 
 
 
 
    Acme
(Hive Bee)
10-25-01 18:19
No 228841
      Re: Piperonyl Chloride Question  Bookmark   

Strike on pp 12o alludes to having 3o g of ZnCl2 for this procedejuere

Don't forget about the Russians with the Benzyl nitrile and EtOAc that would be neat
 
 
 
 
    Rhodium
(Chief Bee)
10-25-01 18:35
No 228846
      Re: Piperonyl Chloride Question  Bookmark   

The "russian" benzyl cyanide/EtOAc reaction does not work well here, as it involves heating in pretty concentrated H2SO4. Don't know if the MD bridge would like that treatment.
 
 
 
 
    Bwiti
(Hive Addict)
10-25-01 22:38
No 228914
      Re: Piperonyl Chloride Question  Bookmark   

  From what I read in Strike's book and from friend's comments, I'm under the impression that at least some of the russian science is bull-shit or weak.

  The christian god hates your soul. Care for a little necrophilia?
 
 
 
 
    Scooby_Doo
(Hive Bee)
10-29-01 15:10
No 230071
      Re: Piperonyl Chloride Question  Bookmark   

Bwiti: Strikes procedure works fine. Yields form memory were in the high 70's. Use the procedure which Strikes ref says not to use ZnCl2 but use it! Keep an eye on the temp it is the key to success with that reaction.

If your going to produce piperonal from the chloride use a large excess of hexamine, when using acetic acid as the solvent. If using alcohol this is not required as the hexamine is not hydrolysed.
 
 
 
 
    Bwiti
(Hive Addict)
10-30-01 08:31
No 230513
      Re: Piperonyl Chloride Question  Bookmark   

  Cool. This entire procedure sounds pretty sweet to me. The only thing I'm worried about is possible suck-back from home-rig generation of HCl. It would be cool if the HCl could be made in situ, but that's wishful thinking..This won't be the first stupid question I've asked: Is there such thing as a suck-back valve? I can't find anything like it in a few of my favorite catalogs.. It's probably been brought up here many times, so I'll check out the search engine.
  Sounds like a plan -> "fish aquarium anti-suck-back valves" - No 225556
  Am I correct in saying that a little H2O wouldn't hurt the reaction?

Peace!cool

  The christian god hates your soul. Care for a little necrophilia?
 
 
 
 
    Scooby_Doo
(Hive Bee)
11-03-01 07:11
No 232608
      Re: Piperonyl Chloride Question  Bookmark   

The only thing I'm worried about is possible suck-back from home-rig generation of HCl.

Yes suck back with this one is a total slut! I ended up having another flask between the hose coming from the reaction flask to the outlet which was bubbling through a 10% solution of NaOH. I didn't have a problem with the HCl generator sucking back. Usually the larger generators have so much HCl being produced it is less of a problem.

Is there such thing as a suck-back valve? I can't find anything like it in a few of my favourite catalogs

There are suck back/one way valves which I have seen in the big company catalogs. I'm sure smaller companies can get them in for you.

Am I correct in saying that a little H2O wouldn't hurt the reaction?

Yes it will reduce yields, bubbling the HCl gas through conic sulfuric acid helps. I never did anything more than that.

Tips that I vaguely remember

The rate of HCl entering the reaction was about 2 drops/sec of sulfuric acid onto the salt/HCl mix.

Soon as the reaction temp hits the mid 20's the reaction should turn a reddish colour. The reaction works best around 28-32 deg. You will need a ice bath to cool the reaction.

When doing the carbonate washes the layers will invert on the first wash.

Piperonyl Chloride is fluro yellow/green in colour with a mp around 20 deg