Synthese von Tetradecano‐14‐lacton durch Ringerweiterung

Synthesis of Tetradecano‐14‐lactone by Ring Enlargement The aldehyde 3 , prepared by ozonolysis of 2‐allyl‐2‐nitrocyclododecanone, gave the ring‐enlargement product 5 (85%) by treatment with (i‐Bu) 2 AlH. Its transformation to the tetradecano‐14‐lactone ( 8 ) via the aldol ester 6 and other routes (best is reduction with Bu 3 SnH, AlBN, toluene) was difficult. Remarkable is the smooth denitrification of 3 (loss of HNO 2 ) to the conjugated dione 4 by chromatography on silica gel or base treatment.