3-Phenyl-l-Menthopyrazole [(4R, 7S)-7-isopropyl-4-methyl-3-phenyl-4,5,6,7-tetrahydroindazole]: A new type of chiral auxiliary

摘要

The preparation and the utility of 3-phenyl-l-menthopyrazole [(4R,7S)-7-isopropyl-4-methyl-3-phenyhl-4,5,6,7-tetrahydroindazole] as a new type of chiral auxiliary are outlined. The synthetic strategies using the auxiliary are summarized in the synthetic loop concept, in which three essential reaction steps are included, as illustrated in Scheme 1.