Asymmetric transfer hydrogenation of unsaturated ketones; factors influencing 1,4- vs 1,2- regio- and enantioselectivity, and alkene vs alkyne directing effects
作者:Thomas H. Hall、Hannah Adams、Vijyesh K. Vyas、K.L. Michael Chu、Martin Wills
DOI:10.1016/j.tet.2020.131771
日期:2021.1
A detailed study has been completed on the asymmetric transferhydrogenation (ATH) of a series of enones using Ru(II) catalysts. Electron-rich rings adjacent to the CO group reduce the level of CO reduction compared to CC. The ATH reaction can readily discriminate between double and triple bonds adjacent to ketones, reducing the double bond but leaving a triple bond intact in the major product.
A transition-metal-free synthetic method of various ynones via decarboxylative alkynylation of α-keto acids is described. The reaction is carried out undermildconditions and exhibits remarkable tolerance of functional groups. The mechanism of a radical process is proposed in the reaction.
General Synthesis of α-Alkyl Ynones from Morpholine Amides and 1-Copper(I) Alkynes Promoted by Triflic Anhydride
作者:Yunxiang Weng、Lin Min、Xiaobao Zeng、Lidong Shan、Xinyan Wang、Yuefei Hu
DOI:10.1021/acs.orglett.0c02944
日期:2020.11.6
The first general method for the synthesis of α-alkyl ynones was developed based on the strategy of electrophilic activation of amides. Its distinctive advantages are attributed to the use of air-stable “bare” 1-copper(I) alkyne as a mild nucleophile without any exogeneous ligand.
[EN] COMPOUND AND METHOD<br/>[FR] COMPOSÉ ET PROCÉDÉ
申请人:UNIV BRISTOL
公开号:WO2013186550A1
公开(公告)日:2013-12-19
A compound of formula (I): (I) wherein Y is, Z is OR10, NR11R11 SR11, S(0)R11 S02R11, R10 is H, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted heterocyclyl, CO-R11, or a protecting group, and R11 is optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted heterocyclyl, or alkoxyl; a process for making a compound of formula (I); and a process for making a prostaglandin or a prostaglandin analogue using a compound of formula (I).
A directC(sp2)H alkynylation of aldehyde C(O)H bonds with hypervalent iodine alkynylation reagents provides ynones under metal‐free conditions. In this method, 1‐[(triisopropylsilyl)ethynyl]‐1,2‐benziodoxol‐3(1H)‐one (TIPS‐EBX) constitutes an efficient alkynylation reagent for the introduction of the triple bond. The substrate scope is extended to a variety of (hetero)aromatic, aliphatic, and α