THE REACTION OF HYDROGALLIUM(III) DICHLORIDE (HGACL2) WITH OLEFINS, ACETYLENES, AND ALPHA,BETA-UNSATURATED KETONES

The reaction of HGaCl2 With 1-octene yields 1-octylgallium(III) dichlo ride in 77% yield, but with 2-octene a 2:1 mixture of 2- and 3-octylga llium dichloride(III) is obtained in 88% yield, and the reaction of (E )-stilbene gives an even more complex mixture. Hydrogallation of 1,4-d iphenylbutadiene with HGaCl2 followed by hydrolysis yields 1,4-dipheny lbutane in 53% yield. The reactions of diphenylacetylene and 4-octyne under the same conditions give (E)-stilbene and (E)-4-octene in 76% an d 63% yield, respectively, while 1-octyne undergoes polymerization. 2- Benzoylstyrene (calcone) reacts with HGaCl2 to give, as the main produ ct, a compound arising from 1,4-addition of the H-Ga bond across the e none system, together with a double hydrogallation product.