Tetrahedron Letters,Vol.26,No.l3,pp 1677-1680,1985 ... Andrew B. McElroy and Stuart Warren* University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW. ... The title compounds (3) were synthesised by stereospecific [1,3] rearrangement, controlled by the Ph PO group, from single isomers of the Horner-Wittig a ducts ... We have recently reported' the synthesis of &hydroxy-allylic ... (3) as intermediates in the synthesis of diene alcohols.