Cyclohexanol acetylation

Likewise, thermolysis of 4-azidophenyl methyl ketone in methanol yields 5-acetyl-2-methoxy-3//-azepine (60%), compared to only an 8% yield from the photolytic reaction.78 119 The thermolysis of phenyl azide in refluxing cyclohexanol yields no 3H-azepine, only diphenyl-diazene (10%) and aniline (30%).74 In contrast, thermolysis of methyl 2-azidobenzoate in cyclohexanol furnishes a mixture of methyl 2-(cyclohexyloxy)-3//-azepine-3-carboxylate (20 % bp 127°C/0.1 Torr) and methyl 2-aminobenzoate (60%). Thermolysis of the azido ester in methanol under nitrogen in an autoclave at 150 C yields a 7 10 mixture (by 1HNMR spectroscopy) of the amino ester and methyl 2-methoxy-3//-azepine-3-carboxylate, which proved to be difficult to separate, and much tar.74 The acidic medium179 is probably responsible for the failure of methyl 2-azidoberjzoate to yield a 3//-azepine when thermolyzed in 3-methoxyphenol aniline (40%) is the major product.74... 

Figure 6.28. Acetylation of cyclohexanol carried out continuously under fluorous biphasic conditions for 500...

Biological. Microbial degradation products reported include cyclohexanol (Dugan, 1972 Verschueren, 1983), l-oxa-2-oxocycloheptane, 6-hydroxyheptanoate, 6-oxohexanoate, adipic acid, acetyl-CoA, succinyl-CoA (quoted, Verschueren, 1983), and cyclohexanone (Dugan, 1972 Keck et al 1989). 

Alcohol carbons are identified by spectral comparison of the alcohol with the corresponding acetate Upon acetylation of cyclohexanols the a-carbons shift about 3 to 4 ppm downfield and the /i-carbons move 2 3 ppm upheld. Esterification of axial hydroxy groups also causes a downfield shift of 1 ppm of the y-carbons [65 a]. 

The reaction of (1) with cyclohexene oxide produces the trans-cyclohexanol derivative (6). Acetylation of (6) followed by mercuric ion-promoted hydrolysis afforded the acetoxy aldehyde (7) in 82% overall from cyclohexenc oxide. 

Wallace, J. E., Schroeder, L. R. Koenigs-Knorr reactions. Part 3. Mechanistic study of mercury(ll) cyanide promoted reactions of 2-0-acetyl-3,4,6-tri-0-methyl-a-D-glucopyranosyl bromide with cyclohexanol in benzene-nitromethane. J. Chem. Soc., Perkin Trans. 21977, 795-802. 

Isomerization of ethynylcarbinols. Rupe12 first observed that ethynylcarbinols when refluxed in formic acid (90%) are isomerized to unsaturated carbonyl compounds, which he considered to be aldehydes. Chanley13 later investigated the reaction in detail and found that the predominant product is an a,/ -unsaturated ketone. Thus 1-ethynyl-l-cyclohexanol (1) is converted mainly into 1-acetyl-l-cyclohexene (2), with onLy traces of (3) being formed. 

The reaction of 2-0-acetyl-3,4,6-tri-0-methyl-a-D-glucopyranosyl bromide and cyclohexanol in benzene-nitromethane in the presence of mercury(ii) cyanide displayed a first-order dependence on the concentrations of the glycosyl bromide and mercury(ii) cyanide, and the rate of the reaction was independent of the concentration of cyclohexanol. The proportion of P-glycoside in the initial products increased as the concentration of cyclohexanol was increased and the p-glycoside appears to be formed directly from carboxonium ion intermediates and by selective... 

Paulsen s group has transformed the protected streptosyl chloride (or bromide) (521 RS = Ph,H) into dihydrostreptosylstreptidine (522) and related pseudo-disaccharides. ° ° The 2,3-0-benzylidene derivatives (521 R R = Ph,H) yielded a-linked glycosides of L-streptose preferentially, whereas the 2,3-carbonates (521 R R = O) gave / -linked glycosides e.g. with cyclohexanol and l,2,3,4-tetra-0-acetyl-)5-D-glucopyranose). ° This work culminated in the synthesis of D-streptobiosamine (523) and its L-enantiomer (a disaccharide unit of streptomycin) by a route that involved condensation of methyl a-o(or L)-strepto-side 3 -(trimethylene dithioacetal) with the nitrosyl chloride adduct of 3,4,6-tri-O-acetyl-D-(or L)-glucal. ... 

Scheme 8 7. The addition of cyclohexanol to ethanoic anhydride (acetic anhydride) with catalysis from hydrogen chloride (HCI). The catalyst is generated in the reaction between ethanoyl chloride (acetyl chloride, CH3COCI), which also (Scheme 8.54) produces cyclohexyl ethanoate (cyclohexyl acetate) at the same time.

Also obtained (low yield) by reaction of 2-acetyl-1,4-benzoquinone with an excess of cyclohexanol at r.t., with exclusion of light [2869]. 

Thiem [29] found that methyl 3,4-di-O-acetyl-D-glucuronal 38 adopts almost exclusively an inverted H4 (d) half-chair conformation. A 60 40 mixture of a-D-ma no-pyranoside 39 [in a flattened (d) boat conformation] and fi-D-gluco pyranoside 40 was obtained when 38 was treated with cyclohexanol and A-iodosuccinimide in acetone (Scheme 9). Other methyl glycuronals h-ribo, u-lyxo and h-xylo) adopt the usual conformation with an equatorial methoxycarbonyl... 

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