Asymmetric intramolecular C–H insertion of sulfonyldiazoacetates catalyzed by Rh(II)

The asymmetric C–H insertion of alkyldiazosulfones has been studied. High selectivity was achieved using a combination of a chiral catalyst and a chiral auxiliary (Rh2(S-pttl)4 and menthyl ester).

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(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl (2R,3R)-tetrahydro-3-methyl-2H-thiopyran-1,1-dioxide-2-carboxylateC17H30O4S90% de[α]D20=-28.7 (c 0.013, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,5R,2′R,3′R)

((2R,3R)-Tetrahydro-3-methyl-2H-thiopyran-1,1-dioxide-2-yl)methanolC7H14O3S[α]D20=-16.7 (c 0.005, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3R)

Ethyl (2S,3S)-tetrahydro-3-methyl-2H-thiopyran-1,1-dioxide-2-carboxylateC9H16O4S[α]D20=+32.5 (c 0.005, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S)

Ethyl (2R,3S)-tetrahydro-3-methyl-2H-thiopyran-1,1-dioxide-2-carboxylateC9H16O4S[α]D20=-36.8 (c 0.003, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3S)

Ethyl 2-((R)-4-(4-toluenesulfonyloxy)pentylsulfonyl)acetateC16H24O7S2[α]D20=+14.1 (c 0.017, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-1,4-Bis(4-toluenesulfonyloxy)pentaneC19H24O6S2[α]D20=+15.1 (c 0.023, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)