876351-58-5Relevant academic research and scientific papers
Asymmetric Oxidative Cyclization of o-Phenolic Oxime-Esters: First Synthesis of Enantiomerically Enriched Spiroisoxazoline Methyl Esters
Murakata, Masatoshi,Tamura, Masafumi,Hoshino, Osamu
, p. 4428 - 4433 (1997)
A new method for the synthesis of enantiomerically enriched cyclohexadienone spiroisoxazoline (-)-2a has been described. Asymmetric intramolecular oxidative cyclization of the o-phenolic oximeester 1c using a novel optically active tertiary alcohol (-)-3 as a chiral auxiliary proceeded smoothly to afford cyclohexadienone spiroisoxazoline 2c in 83% yield. Opitcally active tertiary alcohol (-)-3 was synthesizied from racemic (1S*,8R*,9R*,10R*)-8-phenyl-1-decalol (4) by optical resolution. Removal of the chiral auxiliary in 2c with CF3COOH followed by methylation gave methyl ester (-)-2a in 74% ee (71% chemical yield) having S-configuration. The absolute configuration of 2a was determined by the synthesis of the marine natural product (+)-aerothionin.
