Ynamide Carbopalladation: A Flexible Route to Mono‐, Bi‐ and Tricyclic Azacycles
作者:Craig D. Campbell、Rebecca L. Greenaway、Oliver T. Holton、P. Ross Walker、Helen A. Chapman、C. Adam Russell、Greg Carr、Amber L. Thomson、Edward A. Anderson
DOI:10.1002/chem.201501710
日期:2015.9
Bromoenynamides represent precursors to a diversity of azacycles by a cascade sequence of carbopalladation followed by cross‐coupling/electrocyclization, or reduction processes. Full details of our investigations into intramolecular ynamidecarbopalladation are disclosed, which include the first examples of carbopalladation/cross‐coupling reactions using potassium organotrifluoroborate salts; and an
Reductive Cyclization of Bromoenynamides with Alcohols as Hydride Source: Synthesis and Reactions of 2-Amidodienes
作者:Rebecca L. Greenaway、Craig D. Campbell、Helen A. Chapman、Edward A. Anderson
DOI:10.1002/adsc.201200703
日期:2012.11.26
Under basic conditions in alcoholic solvents, bromoenynamides undergo palladium-catalyzed cyclization to cyclic 2-amidodienes in good to excellent yields. This process represents the first use of an alcohol as a hydride source in an alkynecarbopalladation/termination sequence, with the site selectivity of the reduction showing a strong dependence on the tethering ring size (5–8), and the nature of
Palladium-Catalyzed Cascade Cyclization of Ynamides to Azabicycles
作者:Rebecca L. Greenaway、Craig D. Campbell、Oliver T. Holton、C. Adam Russell、Edward A. Anderson
DOI:10.1002/chem.201102880
日期:2011.12.16
Cascade reactions: A modular assembly of azabicycles by using a cascadecyclization/Suzuki coupling/6π‐electrocyclization of bromoenynamides is reported (see scheme). The reaction offers a wide substituent scope on the bicyclic aminodiene products, which can be selectively oxidized as a general approach to aromatic azabicycles.
A DIRECT METHOD FOR α-METHYLENEBUTYROLACTONE SYNTHESIS USING HOMOALLYL ALCOHOLS
作者:Isamu Matsuda
DOI:10.1246/cl.1978.773
日期:1978.7.5
3-Trimethylsily-3-buten-1-ols (1) are prepared by a ring opening of epoxides with α-trimethylsilvinylmagnesium bromide in the presence of catalytic amounts of CuI. 3-Bromo-3-buten-1-ols (2) derived from (1) react with Ni(CO)4 to give directly α-methylenebutyrolactones (4) with the assistance of potassium acetate in good yields except the case of a cyclopentanol derivative (2e).
Hydroalumination of terminal β-acetylene alcohols with lithium aluminum hydride
作者:O. A. Garibyan、G. M. Makaryan、M. R. Ogannisyan、Zh. A. Chobanyan
DOI:10.1134/s1070363216020109
日期:2016.2
Hydrogenation of terminal β-acetylene alcohols with lithium aluminum hydride in THF has afforded homoallylic alcohols. Decomposition of the intermediate organoaluminum complex with deuterated water, iodine, or pyridinium dibromide has evidenced about the non-regioselective hydride attack at the triple bond.