Asymmetric version of P-S to P-C [1,3]-sigmatropic rearrangement in the ferrocene series

The synthesis of new 2-sulfanylferrocenylphosphonates and derivatives has been achieved through a P-S to P-C [1,3]-sigmatropic rearrangement. The asymmetric version of this reaction has been successfully performed starting from a ferrocenylphosphorodiamidothioate and afforded, as a single diastereoisomer, enantiomerically pure planar chiral ortho-thio-substituted ferrocenyl phosphorodiamidate.

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(3aR,7aR)-2-Sulfanylferrocenyl-(3a,4,5,6,7,7a-octo-hydro-1,3-dimethyl-1,3,2-benzodiazaphosphole)-2-oxideC18H25FeN2OPSEe >99%[α]D20=-163.4 (c 0.74, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R,R)

(3aR,7aR)-[(SFc)-(2-Methylsulfanyl)ferrocenyl]-(3a,4,5,6,7,7a-octo-hydro-1,3-dimethyl-1,3,2-benzodiazaphosphole)-2-oxideC19H27FeN2OPSEe >99%[α]D20=-426.5 (c 0.31, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R,R,SFc)

(RFc)-Diisopropyl 2-[(2S)-2-hydroxypropyl]sulfanylferrocenyl phosphonateC19H29FeO4PSEe >99%[α]D = +196.3 (c 0.40, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (RFc,S)

(SFc)-Diisopropyl 2-[(2S)-2-hydroxypropyl]sulfanylferrocenyl phosphonateC19H29FeO4PSEe >99%[α]D = −106.1 (c 0.33, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (SFc,S)

(RFc)-Diisopropyl[2-((2S)-2-[(tert-butoxycarbonyl)amino]-3-methylbutylsulfanyl)ferrocenyl]phosphonateC26H42FeNO5PSEe >99%[α]D = +66.7 (c 0.33, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (RFc,S)

(SFc)-Diisopropyl[2-((2S)-2-[(tert-butoxycarbonyl)amino]-3-methylbutylsulfanyl)ferrocenyl]phosphonateC26H42FeNO5PSEe >99%[α]D = −64.0 (c 0.285, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (SFc,S)