Palladium-Catalyzed Arylcarboxylation of Propargylic Alcohols with CO<sub>2</sub> and Aryl Halides: Access to Functionalized α-Alkylidene Cyclic Carbonates
trans-oxopalladation of the C≡Cbond by an ArPdX species, and a reductive elimination procedure afforded a series of functionalized α-alkylidene cyclic carbonates in moderate to excellent yields. Notably, the configuration of these tetrasubstituted olefins was dominated by the trans-oxopalladation step where the aryl group derived from ArX is located trans to the oxygen attached in the doublebond. This protocol
ne, copper iodide could efficiently catalyze the coupling of internal propargylicalcohols with carbondioxide to afford the corresponding α‐alkylidene cyclic carbonates in moderate to excellent yields. Moreover, we have developed a new and versatile protocol for the chemo‐ and stereoselective synthesis of a wide range of (E)‐α‐iodoalkylidene cyclic carbonates from carbondioxide, propargylic alcohols
An unexpected thermal-ring-rearrangement of benzochromenes to inden-3-yl-naphthols with <i>p</i>TsOH
作者:Srinivasarao Yaragorla、Tabassum Khan
DOI:10.1039/c8ob02264j
日期:——
Described here is the first report of an unexpected thermal-ring rearrangement (TRR) of benzochromenes to indene derivatives promoted by pTsOH, which proceeds through the protonation of benzochromenes by an acid catalysts followed by ring-opening and ring-closure by an intramolecular Friedel–Crafts cyclization.
A novel regioselective annulation of propargylic alcohols with simple carbazoles for the construction of [3,2,1-jk]carbazole scaffolds is described to be the first example of intermolecular synthesis of [3,2,1-jk]carbazoles from simple carbazoles. In situ synthesis of propargyl alcohols from simple, cheap, and easily accessible ketones has also been developed during the one-pot synthesis of [3,2,1-jk]carbazoles
用于构建 [3,2,1- jk ] 咔唑支架的炔丙醇与简单咔唑的新型区域选择性环化被描述为从简单咔唑分子间合成 [3,2,1- jk ] 咔唑的第一个例子。在 [3,2,1- jk ] 咔唑的一锅法合成过程中,还开发了从简单、廉价且易于获得的酮原位合成炔丙醇的方法。