Methylation of Disaccharides-The disaccharide octaacetate was converted t o the or-glycosyl chloridc with titanium tetrachloride.' By treatment with silver carbonate and methanol t h e glposyl chloride mas converted to the methyl heptaacetyl-8-glycoside. The heptaacetyl compound was methylated in acetone solution with dimethyl sulfate and Xl',,, sodium hydroxide solution using a relatively large clicess oE these reageiits. Thc mcthylatioii was completed by two trcatnients with sodium and methyl iodide according to the procedure of Paccu and 'I'rister.8 ni. p . By this method, methyl hcptarnethyl-~-lactosl~le, 84.5-853", methyl heptainethyl-~-celloliiosidc, m. p. 8%!7.5 , methyl heptairiethyl-8-rrielibioside, in. p. 1Os5 106 , methyl heptatnethyl-P-geritiobioside, r n . p . 105l(16" and niethyl heotainethylmaltoside, 1). p. 143" (0.05 nim.), n p 5l .~l t i Z O , were prqiared. T h e final yields based on disaccharide octaacetate wtrr in all caics 404i0 9; of t h e theoretical
Acknowledgment.--'l'hc authors wish t o espress their appreciation to the Corti Products Refining Company for financial assitarice, to G . E. Hilbert of the U. S . Kortliern Regional ' 7 ) Parsu. ihl
1'
l3t.i.
61, l i 0 S ( 1 9 2 q ) I,,!, ~ < , I > R , - ~6 T 1. , 21:;
,I ! r i ' ( t r
Vinyl Alcohols.
Sunimary 1. *Inwv inethod for the separation of the hydrolysis products of completely methylated disaccharides has been developed. This involves the introduction of azoyl (p-phenylazobenzoyl) groups into the positions opened by hydrolysis. 2. similar method has been developed based on niethyl alcoholysis of methylated disaccharides followed by azoylation of one of the products. 3 . 130th methods have been applied to five con~pletelymethylated disaccharides. 4 Crystalline azoyl derivatives of the eight methyl triInethyl-D-glucopyranosides have been obtained by chromatographic separation of the cy a i d ,3 mixtures. [ < I \A\
~l~!~.?'t
[COU rRIBUTION FROM THE NOYES
Research Laboratory for a generous sample of levoglucosan, atid to B. Clifford Hendricks of the University of h'ebraska for seed crystals of tetrainctliplg,lldctose.
C l T l , IO\\4
RECEIVED S O \ F M I 3 I . R 17, 1944
CAEMICAI. LAIIOKATORY, UNIVERSITY O F I I . L I \ O I S ~
XV.'
Trisubstituted Vinyl Alcohols
BY REYNOLD C.FusoN, L. J. ALMSTKONG, DAVIDH. CIIADWICK, J. \V.\Ys;t: K N E I S L E YSTANLEY ,~ I' ROlVLr\ND,3lv. J. SHENK, JR., A N D QUENTINF. SOPER
The vinyl alcohols dealt with in this series of papers, unique in that they contain only hydrocarbon s ~ b s t i t u e n t s fall , ~ into two separate categories which may be designated as aldehyde enols and ketone enols. The stable aldehyde enols which have been ma& so far are 2,2-diarylvinq-l alcohols in which one or both of the radicals is mesityl or isoduryl. They may be represented by forriiula 1. Ar>C=CiiOH hIcs
I
-I>.
-c
(h1es)OH
?\res
11
The ketone enols differ widely in the tendency to ketonize,s their stability depending on the nature of the three substituents. Those which are stable have a mesityl or a similar radical6iii the beta as well as the cilplm position a ~ i dinay lie represented by formula 11. AIoreos-er, from a consideration of known examples, it appears that A
inny be any hydrocarbon residue but not hythige11.~ The purpose of the present work was to tliseuver the structural elements which are necessnr!. and siitzcient to stabilize this type of enol. Eight n r ~trisubstituted vinyl alcohols have been csarnined in which the structure has been varied systematically. They fall into two classes which may be designated as disubstituted acetophctiones Lind disubstituted acetones.
Enols of Disubstituted Acetophenones The acetophenone eiiols are represented by foriiiu1;ts 111 t u VII.
11".. y=c ~ w l
Tile first of these, %mesityl- l-phenyl-l-propeii1-01 (111), differs structurally from the known
t o this tirnc t h e r e l . ~ t i \ eteritlenc~ei of v i i i y l a l c o h o l s t u niLe h . i r c r i o L bcen nie.i.iircri iicctir:iti.l>.. V n u i i ii hizh caii be t e d , u i r l ch ir:bc.tt?rirv
