Selective ring transformations of 1-[2-(trimethylsilylmethyl)cyclopropylcarbonyl]imidazoles
作者:Toshikazu Hirao、Daisuke Misu、Toshio Agawa
DOI:10.1039/c39860000026
日期:——
The title compounds underwent CsF- or BF3·Et2-induced selective ring-opening reactions leading to the cyclobutanone derivatives or γδ-unsaturated carboxylic acids, respectively.
were successfully used in the Ni(CO)4 -induced carbonylation reactions of gem-dibromocyclopropanes. The nickel carbenoid and enolate complexes are considered to be involved as key intermediates. Protonation afforded the cyclopropanecarboxylic acid derivatives. The presence of an electrophile achieved another stereoselective carbon-carbon bond formation via the nickel enolate intermediate.
Cyclopropyl carbeniods, generated from dibromocyclopropanes and methyllithium, insert preferentially into SiMe(3) activated C-H bonds. In other cases, allene formation remains the dominant process.
Jakoubkova,M. et al., Collection of Czechoslovak Chemical Communications, 1966, vol. 31, p. 979 - 996
作者:Jakoubkova,M. et al.
DOI:——
日期:——
Versatile Synthesis of Diethyl Cyclopropanephosphonates