roamingnome - 24-8-2007 at 11:55
dont want to share old news but I think this raised my eyebrow
http://www.cem.msu.edu/~reusch/VirtualText/Images2/coreduc2....
taylorandfrancis.metapress.com/index/J258R12673408038.pdf
Synth. Commun. 2007, 37, 149
TRANSFORMATION OF ARYL ACYLOIN O-ALKYL AND O-PHENYL DERIVATIVES TO
KETONES
Zhiyi Yao,1 Deju Ye,1 Hong Liu,1 Kaixian Chen,1 and Hualiang Jian1,2
School of Pharmacy, East China University of Science and Technology, Shanghai, China
The treatment of aryl acyloin (a-hydroxyketone) O-alkyl and O-phenyl derivatives with 2–3 equiv of Zn
and 1–2 equiv of NH4Cl in ethanol, refluxing for 20–120min, gave the corresponding ketones with
excellent yields. Further, a,b-epoxy ketones can be efficiently transformed to b-hydroxy ketones, and 2,2-
dialkoxy-1-phenyl ketone also can be dealkoxylated to 1-phenyl ketone
I have been trying to study the reactions of acyloins with urea and have found a wealth of information.
Which I will not dump forth at this time….
But the above techniques just found may be of high interest for any that seek benzyl methyl ketone from acyloins such has pac.
If the ketone ends up in the beta and NOT alpha position.
http://www.origin-life.gr.jp/3201/3201053/3201053.html
this link shows the possibly of obtaining the l-pac urea. If the reaction is run to hot or long oxazolones are formed.
roamingnome - 28-8-2007 at 09:08
onyldouble posting for overall clearity ...
Abstract;.ALPHA.,.BETA.-Unsaturated Ketones are well recognized as an important unit in organic syntheses. One representative method for the
preparation of .ALPHA.,.BETA.-unsaturated ketones is the dehydration of the corresponding .BETA.-hydroxy ketones (aldols). The dehydration of
.ALPHA.-hydroxy ketones (acyloins), however, is very difficult, because the cation of .ALPHA.-position of ketones hardly generates. To raise up the
leaving ability, we chose acyloin aulfonates, which successfully underwent the desired elimination to give .ALPHA.,.BETA.-unsaturated ketones.
http://sciencelinks.jp/j-east/article/200424/000020042404A08...
3. Inokuchi, T.; Kawafuchi, H.; Torii, S. Removal of a-hydroxy group of acyloins
and their derivatives with vanadium(II)–THF complex. Chem. Lett. 1992, 21
so it is shown here that it is possible under some chemical regime... but is it possible with facile reagents such as zinc and ethnaol ..will remain
to be proven later..
bye...