Phosphonoselenoic acid esters from the reaction between phosphoroselenoyl chlorides and Grignard reagents: synthetic and stereochemical aspects

Abstract

Substitution reactions between a phosphoroselenoyl chloride and Grignard reagents proceeded smoothly at the phosphorus atom to furnish phosphonoselenoic acid esters in moderate to high yields.

Asymmetric synthesis of organophosphorus compounds using H–P reagents derived from chiral alcohols

“…In continuation of their interest in the use of BINOL-derived phosphonoselenoyl chloride (38), Murai et al reported on the reaction of (S)-38 with Grignard reagents. 71 The use of chiral Grignard reagents (in the racemic form) such as sec-butylmagnesium bromide (44a), sec-decylmagnesium bromide (44b) and 2-ethylhexylmagnesium bromide (45) led to desired products 46a,b and 47 as mixtures of diastereoisomers albeit with no diastereoselectivity (Scheme 16). The diastereomers could however be easily distinguished by 31 P NMR and separated by simple chromatography or crystallization.…”

“…In the case of 46a, the absolute configuration of the stereogenic carbon was found to be S, as determined by X-ray analysis (Scheme 16). 71 Recently, Murai and co-workers reported on the use of (S)-BINOL-derived phosphonoselenoates 48 and phosphonates 50…”

“…In the case of 46a , the absolute configuration of the stereogenic carbon was found to be S , as determined by X-ray analysis (Scheme 16). 71…”

Sequential Deprotonation–Alkylation of Binaphthyloxy-Substituted Phosphonochalcogenoates: Chiral Tri- and Tetrasubstituted Carbon Centers Adjacent to a Phosphorus Atom

“…In contrast, substantially less attention has been paid to phosphonates such as IIc , despite the fact that the binaphthyloxy group in IIc exerts a strong influence on the stereochemical fate of the carbon atom connected to the phosphorus atom (Scheme a, method d). Indeed, our recent studies showed that the chirality of the α carbon atoms relative to the phosphorus atom in phosphonochalcogenoates III can be discriminated by 31 P NMR spectroscopy . Moreover, carbanions at these positions may exhibit chirally distinct environments.…”

“…Indeed, our recent studies showed that the chirality of the α carbon atoms relative to the phosphorus atom in phosphonochalcogenoates III can be discriminated by 31 P NMR spectroscopy. 13 Moreover, carbanions at these positions may exhibit chirally distinct environments. Herein, we report the sequential deprotonation−alkylation of phosphonochalcogenoates III (Scheme 1c).…”