Allylic hydroxy phosphonates are versatile intermediates for the asymmetric synthesis of natural products and enzyme inhibitors. A variety of substituted allylic hydroxy phosphonates and the carbonate derivatives can be prepared via cross metathesis of phosphonates 1 and 2 with subsubstituted alkenes. Thus, a large scale synthesis of enantiomerically pure phosphonates (1 and 2) was required. The stereospecific palladium catalyzed addition of oxygen nucleophiles to phosphono allylic carbonates results in the efficient stereoselective synthesis of tetrahydrofurans and pyrans; the crucial chiral, nonracemic building blocks for the synthesis of biologically active molecules such as (-)-centrolobine.