The Absolute Configuration of Sulfoxides and Sulfinates

The absolute configurations of (-)-menthyl (-)-(S)-p-iodobenzenesulfinate and (-)-(R)-3-methylsulfinylpropylamine have been linked by a synthetic sequence involving an odd number of Grignard displacement reactions; consequently, this displacement has been rigorously shown to proceed with inversion of configuration at sulfur. This sequence, joined to present and earlier intercorrelations of sulfinates and sulfoxides, serves to establish absolute configurations in this series of compounds. The absolute configuration of (+)-methyl allyl sulfoxide, a key relay compound in the sequence, has been reassigned. Some apparent discrepancies which appeared in the earlier literature and which bear on the present work have been resolved.