Catalytic Synthesis of n-Alkyl Arenes through Alkyl Group Cross-Metathesis
摘要:
n-Alkyl arenes were prepared in a one-pot tandem dehydrogenation/olefin metathesis/hydrogenation sequence directly from alkanes and ethylbenzene. Excellent selectivity was observed when ((PCP)-P-tBu)IrH2 was paired with tungsten monoaryloxide pyrrolide complexes such as W(NAr)(C3H6)(pyr)(OHIPT) (1a) [AT = 2,6-i-Pr2C6H3; pyr = pyrrolide; OHIPT = 2,6-(2,4,6-i-Pr3C6H2)(2)C6H3O]. Complex 1a was also especially active in n-octane self-metathesis, providing the highest product concentrations reported to date. The thermal stability of selected olefin metathesis catalysts allowed elevated temperatures and extended reaction times to be employed.