Oxidation during reductive cyclisations using Bu3SnH
作者:W.Russell Bowman、Harry Heaney、Benjamin M. Jordan
DOI:10.1016/s0040-4020(01)96061-2
日期:1991.1
Reductivecyclisations using Bu3SnH include an “oxidation” step if the removal of an acidic proton from the intermediate cyclised radical, by Bu3SnH acting as a base, is favourable. A “pseudo” SRN1 mechanism is proposed.
如果通过Bu 3 SnH作为碱从中间环化自由基中除去酸性质子是有利的,则使用Bu 3 SnH进行的还原环化包括一个“氧化”步骤。提出了一种“伪” S RN 1机制。
Effect of oxygen substituents on the regioselectivity of the Pd-assisted biaryl coupling reaction of benzanilides
This study investigated the effect of oxygen substituents in the benzoyl part of N-(2-iodophenyl)benzamide on the coupling position in its Pd-assisted biaryl couplingreaction. Benzamide with methylenedioxy and acyloxy groups yielded the ortho-product formed predominantly by connection to a more hindered carbon. The mechanism is discussed from the perspectives of both steric and coordinated effects
The direct arylation of benzanilide (1) possessing ether oxygen(s) in benzoyl part was examined under phosphine ligand-free conditions, which afforded ortho-product (2) and para-product (3) in very similar ratio to presence of P(o-Tol)(3) conditions. This results suggest that bulkiness of palladium under phosphine-free conditions would be comparable to that of P(o-Tol)(3) conditions.