Mercuration of Carbohydrate Olefins

A convenient procedure for converting carbohydrate derivatives into cyclohexanone analogs (as illustrated in Fig. 8.28) was first observed when the unsaturated sugar 97 was treated in refluxing aqueous acetone with a molar equivalent of mercury (II) chloride [41]. 

This procedure introduced by Ferrier, involving the mercury salt-mediated ring transformation of 6-deoxyhex-5-enopyranosides into deoxyinososes, has provided a route of wide practical utilization in the field of aminocyclitols [42 6] and pseudo-sugar chemistry [47, 48]. This procedure has led to the preparation [49] of the B-A ring system of the antibiotic b-rhodomycin and has extended [50] to thioglycoside analogs of hex-5-enopyranosides (Fig. 8.29). 

Laszlo et al. [51] have treated methyl 3-azido-4-0-benzoyl-2,3,6-trideoxy-p-D-eryt/iro-hex-5-enopyranoside 103 with an equimolar amount of mercuric chloride in refluxing aqueous acetone [41] and obtained in 78 % yield the crystalline 2-benzoyloxy-5-hydroxycyclohex-2-en(Mie 104 instead of the expected 3-azidocyclohexanone 105 G g. 8.30). 

This and previous results are in accord with the finding of Lukacs et al. [55, 56] that an apparent relationship between the stereochemistry at the C5 carbon of the cyclohexanone derivatives produced in the Ferrier reaction and the conformation of 

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