Manufacture of alkene from alkane, said alkene of an equal number of carbons as its alkane precursor, comprising contacting alkane with oxygen in the presence of a boric acid at an elevated temperature, spearating the resultant alkylborate esters from the reaction product, pyrolyzing said alkylborates in an inert atmosphere, preferably in the presence of a methanol or trimethylborate and recovering the formed alkene from the pyrolysis mixture, said recovery preferably including contacting said formed alkene with silica gel.