名称:
Stereoselective Synthesis ofcis-p-Menth-8-ene-1,7-diol,cis-p-Menthane-1,7-diol, andcis-p-Menthane-1,7,8-triol
摘要:
AbstractThe natural products cis‐p‐menthane‐1,7‐diol (cis‐IV), cis‐p‐menth‐8‐ene‐1,7‐diol (cis‐I) and cis‐p‐menthane‐1,7,8‐triol (cis‐II) are obtained starting from the corresponding cis‐cyanohydrins, cis‐2 and cis‐7, respectively, by chemical transformation of the cyano into the hydroxymethyl group. The key step of the synthesis is the very high cis‐selectivity (≥ 96 %) of the MeHNL‐catalyzed HCN addition to 4‐alkylcyclohexanones. From 4‐isopropylcyclohexanone (1) the cyanohydrin cis‐2 and from 4‐(1‐methylvinyl)cyclohexanone (6) the cyanohydrin cis‐7 result almost quantitatively. Regioselective hydroxylation of cis‐I affords the triol cis‐II. X‐ray crystal structure determinations of the final products confirm their cis‐configuration.