Addition reactions apply to alkenes and alkynes. It undergoes many reactions including Diels-Alder additions to electrophilic alkenes and alkynes. Hydrostannylation of alkynes or alkenes provides many derivatives. Hydrogenation of alkenes produces the corresponding alkanes. The mechanism of metal-catalyzed hydrogenation of alkenes and alkynes has been extensively studied. Missing in petroleum are alkenes and alkynes. Oleic acid undergoes the reactions of carboxylic acids and alkenes. Reduction of alkynes is a useful method for the stereoselective synthesis of disubstituted alkenes. Many higher alcohols are produced by hydroformylation of alkenes followed by hydrogenation. These dipoles add to electrophilic alkenes readily. The former converts alkenes, hydrogen, and carbon monoxide into aldehydes. Alcohols add to electrophilically activated alkenes. Olefin metathesis involves little change in enthalpy for unstrained alkenes. NOCl converts some cyclic amines to the alkenes. Hydrocyanation is an industrial method for producing nitriles from hydrogen cyanide and alkenes.