Lossen Rearrangement vs C–N Reductive Elimination Enabled by Rh(III)-Catalyzed C–H Activation/Selective Lactone Ring-Opening: Chemodivergent Synthesis of Quinolinones and Dihydroisoquinolinones
作者:Mengyao Bian、Hamdulla Mawjuda、Hui Gao、Huiying Xu、Zhi Zhou、Wei Yi
DOI:10.1021/acs.orglett.0c03734
日期:2020.12.18
An unprecedented Rh(III)-catalyzed cascade C–H activation/Lossen rearrangement of aromatic amides with methyleneoxetanones has been realized along with a tunable C–N bond reductive elimination/trans esterification, giving divergent access to quinolinones and dihydroisoquinolinones via selective ring-opening of the four-membered lactone unit. Combined computational and experimental mechanistic studies
Rhodium(<scp>iii</scp>)-catalyzed formal oxidative [4 + 1] cycloaddition of benzohydroxamic acids and α-diazoesters. A facile synthesis of functionalized benzolactams
A Rh(III)-catalyzed oxidative [4 + 1] cycloaddition of benzohydroxamic acids and α-diazoesters is achieved to afford benzolactams in up to 93% yields. With the N-OAc amido moiety as a directing group, the ortho-C–H is selectively functionalized and the catalytic reaction exhibits excellent tolerance to different functional substituents. A notable rhodacyclic complex is isolated and structurally characterized
Condition-dependent transformations between hydroximic acids and thioaceticacid were achieved. Using NH4HCO3 in the ethanol solvent, efficient N–O bond cleavage of hydroxamic acids occurred to afford primary amides with high functional group compatibility. The reaction was switched to O-acylation when NEt3 and H2O were used as the base and solvent, respectively. These facile transformations could
Neunhoeffer,O.; Gottschlich,R., Justus Liebigs Annalen der Chemie, 1970, vol. 736, p. 100 - 109
作者:Neunhoeffer,O.、Gottschlich,R.
DOI:——
日期:——
Regio-Selective Formation of<i>O</i>-Acyl/<i>O</i>-Benzoyl Hydroxamates by Using a Polymer Supported Reagent Strategy
作者:A. S. Burungule、S. P. Bondge、S. B. Munde、V. E. Bhingolikar、R. A. Mane
DOI:10.1081/scc-120020206
日期:2003.6
Rapid, quantitative and regioselective O-acylation/O-benzoylation of hydroxamic acids has been carried using polymer supported hydroxamate anions and acetyl/benzoyl chloride under mild conditions. The isolation of unambiguous and pure products by simple work-up is also an important feature of this method.