Synthesis of a, w-epoxyaldehydes by hydroformylation of alpha, beta-epoxyalkenes

Linear a,w-epoxyaldehydes with variable distance between the two functional groups, a class of interesting cross-linking agents for proteins, polysacharides and other polymeric compounds, can be conveniently prepared by hydroformylation of commercially available a,w- epoxyalkenes catalyzed by rhodium/phosphine complexes. For example, 1,2- epoxyhex-5-ene (2b) was converted into 6,7-epoxyheptanal (1b) with 75-99% yields in the presence of the catalytic system HRh(CO)(PPh3)3/Xantphos at 20 atm (CO/H2 = 1) and at 40°-100°C. Operating at 40°C practically regiospecific formation of the linear epoxyaldehyde was found.