Enantiomerically pure zinc phosphonates based on mixed phosphonic acid–phosphine oxide chiral building blocks

The coordination chemistry of enantiomerically pure phosphonic acids H2O3PCH2P(O)(C6H5)(R) R = CH3 and C2H5 with zinc is described. The structures of two new optically active layered zinc phosphonates (R)-α-Zn(O3PCH2P(O)(C6H5)(CH3)) and (R)-α-Zn(O3PCH2P(O)(C6H5)(C2H5))·H2O were determined, in which the phosphine oxide is coordinated to zinc. This coordination can be avoided when the synthesis is performed in a slightly acidic medium, as evidenced by the structure of (R)-β-Zn(O3PCH2P(O)(C6H5)(CH3))·H2O.