5
24
M. EDELSON-AVERBUKH AND A. MANDELBAUM
Scheme 16
benzyl alcohol, obtained by reduction of methyl ben-
Isomeric a-tolylbenzyl alcohols 37È39 were synthe-
sized by Grignard reaction of phenylmagnesium
bromide with the corresponding tolualdehydes.
Isomeric a-bromoditolyls 31È33 were prepared by
bromination of 4,4@-, 3,3@- and 2,2@-dimethylbiphenyls
with N-bromosuccinimide (NBS).32
zoate with LiAlD .
4
Dibenzyl esters 20, 21, 25 and 26 were obtained by
trans-esteriÐcation of the corresponding methyl diesters
with benzyl alcohol in the presence of PTSA (cis- and
trans-1,4- and 1,3-dimethyl-1,4- and 1,3-bis(methoxy-
carbonyl)cyclohexanes were prepared by methylation of
the methyl analogs of cis- and trans-18 and -19 with
iodomethane and lithium diisopropylamide in
tetrahydrofuran26).
1-Bromo-1,2-diphenylethane (30) was prepared from
1,2-diphenylethane by NBS bromination.32
Di-2,4,6-trimethylbenzyl esters cis- and trans-40 were
prepared by acylation of 2,4,6-trimethylbenzyl alcohol
with the corresponding acid dichlorides in the presence
of
4-N,N-dimethylaminopyridine
(DMAP)
alcohol
in
was
Acknowledgements
toluene.27,28
2,4,6-Trimethylbenzyl
obtained by reduction of mesitoic acid29 with LiAlH .
4
This work was supported by the Fund for Promotion of Research at
the Technion. We are grateful to Dr V. Ryaboy for his help with the
computer-aided analysis of the CID spectra and to Mr A. Etinger for
assistance with the mass spectral measurements.
The synthetic procedure30,31 used for preparation of
isomeric benzylbenzyl alcohols 35 and 36 is outlined in
Scheme 16.
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