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Stereoselective Synthesis of cis ‐ p ‐Menth‐8‐ene‐1,7‐diol, cis ‐ p ‐Menthane‐1,7‐diol, and cis ‐ p ‐Menthane‐1,7,8‐triol
Author(s) -
Kobler Christoph,
Effenberger Franz
Publication year - 2005
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200401147
Subject(s) - diol , cyanohydrin , chemistry , triol , stereochemistry , regioselectivity , synthon , stereoselectivity , hydroxylation , ene reaction , hydroxymethyl , organic chemistry , catalysis , enzyme
The 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.