Generation of metalloenamines by carbon–carbon bond formation: ring opening reactions of 2-methyleneaziridines with organometallic reagents
作者:Jerome F. Hayes、Michael Shipman、Heather Twin
DOI:10.1039/b005623p
日期:——
Ringopening of 2-methyleneaziridines with Grignard reagents in the presence of CuI yields metalloenamines in a regiospecific fashion which can be further reacted with electrophiles to produce functionalised ketones via a one-pot process.
在 CuI 存在下用格氏试剂开环 2-亚甲基氮丙啶以区域特异性方式产生金属烯胺,该金属烯胺可以进一步与亲电试剂反应,通过一锅法生产官能化酮。
Multicomponent Reactions Involving 2-Methyleneaziridines: Rapid Synthesis of 1,3-Disubstituted Propanones
作者:Jerome F. Hayes、Michael Shipman、Heather Twin
DOI:10.1021/jo016164v
日期:2002.2.1
metalloenamine (metalated imine) intermediate in a regiocontrolled manner. The sequential formation of two new intermolecular carbon-carbon bonds in this reaction provides a rapid entry into a variety of 1,3-disubstituted propan-2-ones, including 11 and 14-23. The scope and mechanism of this multicomponent reaction (MCR) has been assessed. It is established that this MCR tolerates alkyl, aryl, and benzylic Grignard
Multisubstituted Cyclohexene Construction through Telescoped Radical-Addition Induced Remote Functional Group Migration and Horner–Wadsworth–Emmons (HWE) Olefination
作者:Xing-Gui Zhang、Xin Li、Chi Zhang、Chao Feng
DOI:10.1021/acs.orglett.1c03821
日期:2021.12.17
photoredox-promoted alkene difunctionalization via remotefunctional group migration with concomitant intramolecular Horner–Wadsworth–Emmons (HWE) olefination. The characteristic feature of this protocol resides in the fact that the follow-up requiring ketone functionality for ring-closing olefination is in situ unveiled from the otherwise inert tertiary alcohol by the preceding alkene difunctionalization
Conversion of Weinreb Amides into Benzene Rings Incorporating the Amide Carbonyl Carbon
作者:Derrick L. J. Clive、Mai P. Pham
DOI:10.1021/jo802629w
日期:2009.2.20
Esters, acids and acid chlorides can be converted via the intermediacy of their Corresponding Weinreb amides into benzene derivatives that incorporate the original carbonyl carbon as part of the benzene ring. The process involves treatment of the derived Weinreb amides with 3-butenylmagnesium bromide and an allylic Grignard reagent, followed by ring-closing metathesis, dehydration and dehydrogenation. The dehydration-dehydrogenation can be done under acidic conditions with a mixture of TsOH center dot H2O and DDQ or in two steps with SOCl2/Pyridine, followed by treatment with DDQ. Application of the method to carbohydrates provides a convenient route to C-5 aryl pyranosides.
Reductive opening of cyclopropylogous α-hydroxy aldehydes and ketones by samarium(II) iodide
作者:Alex Nivlet、Valérie Le Guen、Luc Dechoux、Thierry Le Gall、Charles Mioskowski
DOI:10.1016/s0040-4039(98)00063-x
日期:1998.4
The regioselectivity of the reductive opening of cyclopropylogous alpha-hydroxy carbonyl compounds using SmI2 in THF or THF-HMPA was studied and shown to depend strongly on the substrate. In some cases, a tandem cyclopropyl opening-deoxygenation reaction afforded the corresponding gamma-keto alkenes in one step. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.