compound2

Katalin Sagi Katalin: This looks great! It is a nice use of the reactions that we have learned. Bruce Bondurant

3,4-dimethylhexa-1,5-diyne-3,4-diol via the Wurtz Reaction Alex Kravetz, Shaun Alvarado 1) Preparation of acetyl bromide from PBr3 and acetic acid 2) Symmetric coupling of acetyl bromide via the Wurtz reaction [1] to form 2,3-butanedione[2] 3) Preparation of sodium acetylide via sodium amide 4) Reaction of sodium acetylide with 2,3-butanedione to form product

[1] [] [2] 2,3-butanedione is a natural product of fermentation and could simply be distilled from yeast and sugar in water That's a good point about biosynthesis. It has a nice buttery, smell too. This scheme is simple and elegant, I have my doubts, though about the Wurtz reaction with acyl halides, It looks like it is most applicable to alkyl halides The nucleophilic anion would be strongly destabilized on the carboxyl carbon. Here is a paper that does show direct coupling of an alpha diketone This one might work well Look at the possibility of treating 1,1,1 tribromoethane with a alkaline or alkaline earth metal to give you a carbene through alpha elimination, then this could possibly couple to form the alpha hydroxy ketone after hydrolysis. Bruce Bondurant



I was able to find a reference in a Russian journal that uses the following reaction in 73% yields: (CH3C2)3Ge2Mg + CH3CH2C=OBr --> CH3CH2C=OC=OCH2CH3 Exactly what I need to do here except they use propanoyl bromide instead of acetyl bromide.

ICR Rxn #977197ICR Doc #85-002453Author: Rybin L. I., VyazankinaText: Zh. Obshch. 1984, 54, Pg 2025-2031 Journal Name: Zh. Obshch Khim

Revised initial formation of the diketone:

I don't know how it works, but it looks good. I'l buy it. Bruce Bonduran