155862-09-2Relevant articles and documents
Transition metal-promoted reactions of boron hydrides. 14. A new synthetic route to B-substituted mono-, di-, and trialkylborazines, B-vinyl-B,B-dialkylborazines, and B-alkylpolyborazylenes via rhodium-catalyzed borazine/olefin hydroboration reactions
Fazen, Paul J.,Sneddon, Larry G.
, p. 2867 - 2877 (2008/10/08)
The RhH(CO)(PPh3)3-catalyzed reactions of borazine with a variety of olefins, including ethylene, propene, 1-butene, cis- and trans-2-butene, 3,3,3-trifluoropropene, styrene, α-methylstyrene, and 4-allylanisole, have been found to give the mono-, di-, and tri-B-alkylborazines in excellent yields. The reactions proceed at room temperature, with low catalyst concentrations, and the degree of substitution is controlled by altering the reactant ratios and reaction times. Unsymmetrically substituted tri-B-alkylborazines are produced by the catalyzed reaction of mono- or di-B-substituted borazines with a different olefin. B-Vinyl-B,B-dialkylborazines are prepared by the reaction of di-B-alkylborazines with acetylene in the presence of catalyst. The catalyzed reaction of borazine with 1,3-butadiene gives a mixture of monohydroboration products, but reaction with 1,5-hexadiene yields mono- and dihydroboration products and a (B3N3H4)-[(CH2)6] 1.22 polymer. The catalyzed reaction of di-B-propylborazine with 1,5-hexadiene gives only the dihydroboration product 1,6-bis(2,4-dipropyl-6-borazinyl)hexane. RhH(CO) (PPh3)3 is also used to catalyze direct alkylation of borazine-based polymers. Thus, the catalyzed addition of either ethylene or propene with polyborazylene, (B3N3H~4)*. yields the B-alkylated polymers (C2H5)y(B3N3H ~4-y) and (C3H7)y(B3N3H ~4-y), respectively.