Asymmetric Synthesis of Protected 1,2-Amino Alcohols Using tert-Butanesulfinyl Aldimines and Ketimines

Abstract

tert-Butanesulfinyl aldimines and ketimines bearing an alpha-benzyloxy or alpha-silyloxy substituent serve as precursors in the synthesis of protected 1,2-amino alcohols in high yields and diastereoselectivities. General protocols are described for the addition of unbranched alkyl, branched alkyl, and aryl organometallic reagents to N-sulfinyl aldimines 1 and 2 and ketimines 5 and 6. Furthermore, the selective N- or O-deprotection of sulfinamide products 3, 4, 7, and 8 is described, enabling further synthetic transformations of the reaction products.

Enantioselective Reduction of Ketones and Imines Catalyzed by (CN‐Box)ReV–Oxo Complexes

“…The amino alcohols were (1) obtained through the reduction of the corresponding amino acid or (2) synthesized by the methods developed by Sharpless [xxiii] or Ellman. [xxiv] The amino alcohols were condensed with diethyl malonimidate dihydrochloride to produce the corresponding bis(oxazoline). Following protocol developed by Corey and Wang, the bis(oxazoline) was deprotonated with n BuLi and treated with p -toluenesulfonyl cyanide to yield the aryl and alkyl substituted cyanonbis(oxazolines) (Scheme 2).…”

Concise asymmetric synthesis of (−)-deoxoprosophylline

“…The SmI 2 -induced cross-coupling of 10 with (S)-N-tert-butanesulfinyl imine 9, which was easily prepared from chiral N-tertbutanesulfinamide, 11 gave hydroxymethyl b-amino alcohol 12a with high diastereoselectivity (>99%, de) in 89% yield. After removal of the chiral auxiliary, the resulting amino alcohol was easily cyclized in one pot under TEA conditions to produce 13 in 80% …”

Functionalization of Mesoporous Carbon with Superbasic MgO Nanoparticles for the Efficient Synthesis of Sulfinamides

“…[20,21] Furthermore, sulfinamides can also act as an N-sulfinyl protecting group, which can be easily removed under mild conditions. [22][23][24] Various procedures have been reported for the preparation of sulfinamides from sulfinic acids, [25] sulfinates, [26][27][28][29] sulfinyl chlorides, [30] disulfides, [31] and by hemolytic substitution at the sulfur atom. [32] However, these reactions often require two or more synthetic steps.…”