Application of novel sulfonamides in enantioselective organocatalyzed cyclopropanation

Three novel aryl sulfonamides derived from (2S)-indoline-2-carboxylic acid have been obtained and used as organocatalysts. The catalysts incorporate diverse functionality on the phenyl ring, enabling steric, and electronic fine tuning of the catalysts. The catalysts facilitate the reaction between a range of α,β-unsaturated aldehydes and sulfur ylides, thus providing cyclopropane products in enantiomeric excesses of up to 99%.

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(S)-N-[(4-Nitrophenyl)sulfonyl]indoline-2-carboxamideC15H13N3O5S[α]D23=+5.5 (c 1.0, MeOH)

(S)-N-[(4-Methylphenyl)sulfonyl]indoline-2-carboxamideC16H16N2O3S[α]D23=-5.4 (c 1.0, MeOH)

(S)-N-[(2,4,6-Triisopropylphenyl)sulfonyl]indoline-2-carboxamideC24H32N2O3S[α]D23=-47.2 (c 1.0, MeOH)