| abstract |
Racemic and optically active cycloaliphatic 2,2,6-trimethyl-cyclohexanecarboxaldehydes, also known as dihydrocyclocitral, are prepared by a novel process consisting in the cyclization of enol esters of formula <IMAGE> (I) wherein the wavy line defines a C-O bond of cis or trans configuration, X represents an acyl group or P(O)(OR)2, wherein R stands for a lower alkyl monovalent radical or an aryl, and Z represents a monovalent radical of formula CHC(CH3)2, i. <IMAGE> ii. <IMAGE> iii. by means of an acid cyclization agent. |