126724-92-3Relevant academic research and scientific papers
Investigations of the metal halide catalyzed alkylation reactions of pentaborane(9)
Gaines, Donald F.,Lee, Laura K.
, p. 1748 - 1758 (1990)
A high-yield route to 1-(isopropyl)pentaborane(9) (1-(i-C3H7)B5H8) has been developed with use of the early-transition-metal halides HfCl4 and ZrCl4 as alkylation catalysts. Comparison studies of the effect of various catalysts and reaction conditions on the catalyzed propylation reaction are discussed. The ZrCl4-catalyzed alkylation of pentaborane(9) (B5H9) with n-ClC3H7, i-ClC3H7, n-ClC4H9, s-ClC4H9, and various butenes produces 1-(alkyl)pentaborane(9) compounds in which the secondary alkyl isomer is favored irrespective of the alkyl source. The effect of the ZrCl4 catalyst and Lewis bases on the isomerization of 1-(i-C3H7)B5H8 and 1-(n-C3H7)B5H8 to the other 1-(propyl)pentaborane isomer, and to 2-(propyl)penta-boranes, was also investigated. In the n-propyl chloride alkylation the isomerization of the propyl group appears to occur prior to substitution onto pentaborane, while in the isopropyl chloride case, the isomerization may arise from catalyst interaction with 1-(i-C3H7)B5H8. The utility of ZrCl4 and HfCl4 catalysts for B5H9 alkylation with MeCl, EtCl, cyclopentyl chloride, cyclohexyl chloride, CH2Cl2, and 2,3-Cl2C4H8 was also examined.
