1 0 to about 20 mg kg day the following examples are given by way of illustration and are not to be construed as limitations of this invention many variations of which are possible within the scope and spirit thereof in a 500 ml 4 necked round bottom flask equipped with a stirrer thermometer n 2 inlet and addition funnel methyl triphenylphosphonium bromide 25 7 g 0 072 mol 1 25 equiv was slurried in 77 ml thf tetrahydrofuran and cooled in an acetone wet ice bath n butyllithium 43 2 ml of 1 6n in hexane 0 069 mol 1 20 equiv was placed in the addition funnel with the slurry initially at 8 u00b0 c the butyllithium was added over 1 hour as the temperature rose and was held at u00b1 1 u00b0 c the mixture was stirred an additional 0 5 hour at 0 u00b0 2 u00b0 c to assure complete formation of intermediate methylenetriphenylphosphorane in a thin suspension of libr the aldehyde product of preparation 2 14 1 g 0 0576 mol in 14 ml thf was added portionwise over 40 minutes maintaining the temperature at 3 u00b0 7 u00b0 c after stirring an additional 15 minutes no starting aldehyde was detected by tlc using 3 1 hexane ether as eluant rf starting aldehyde 0 6 rf product 0 95 the reaction mixture was warmed to ambient temperature and diluted with 150 ml ethylacetate and 90 ml h 2 o the organic layer was separated and washed 2 u00d7 100 ml h 2 o the three aqueous layers were combined and backwashed with 40 ml ethyl acetate the organic layers were combined dried over mgso 4 and stripped to an.