Diol mono

C,gHigO,S Diol mono-tosylate Mech. Study (35)(36) T102... 

A. Alkaline Hydrolysis VI 1,2-Diol Mono alkyl- and Momoaiyl ... 

Carboxylic ookl cleavage of ecmicyelie and alicyclic epoxides is amply exemplified in the literature. Oxidation of methyleneoyolo-hexane with perforraic acid, for example, yields a 1,2-diol mono-formate, from which may be obtained 1-hydroxymethylcyclohexanol... 

Reductive deoxygenation-rearrangement of 2-yne-l,4-diols to 1,3-dienes is a useful synthetic procedure since a large variety of ynediols are available in a few steps by sequential reaction at both ends of acetylene with aldehydes. Acetylenic 1,4-diols can be deoxygenated reductively by lithium aluminium hydride to form conjugated dienes of high stereoisomeric purity (equation 9). A modification to this procedure is the use of acetylenic 1,4-diol mono-THP derivative. Allenic tertiary alcohols which are intermediates in the reaction can be separated and subjected to reductive elimination rearrangement... 

The 1,4-elimination of 193, given in the Eqs. 52 and 53, represents two pathways leading to two different iminium ions 194 and 195, whose relative distribution will depend on whether the reaction is performed under thermodynamic or kinetic control. The species 194 is a cyclooctene derivative and the species 195 a cyclohexane derivative. The cyclohexane derivative 195 must, of course, predominate in a thermodynamically controlled reaction. Like the species 193, the species 196 also represents two pathways for 1,4-elimination as shown in Eqs. 54 and 55. Fortunately, both the pathways yield the same product 197. The reactions shown in Eqs. 56 and 57 are examples of elimination resulting from the 1,3-diol mono-tosylate system. An electron pair orbital on the hydroxylic oxygen that is antiperiplanar to the cleaving central ac c bond provides the necessary electronic push in which the former makes the latter weak, and therefore labile for cleavage. The reaction shown in Eq. 57 was used by Corey and coworkers in a synthesis of... 

Accordingly, the desired diol mono ethers 34 were synthesized in high yields with complete regiocontrol by the reaction of aldehydes with y-alkoxy allyl indium reagents (35 — 34a) (Scheme 9) (07OL953, 08T809). Acylation... 

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