Nickel-Catalyzed Deaminative Acylation of Activated Aliphatic Amines with Aromatic Amides via C–N Bond Activation
作者:Chu-Guo Yu、Yutaka Matsuo
DOI:10.1021/acs.orglett.9b04497
日期:2020.2.7
reductive deaminative cross-electrophile coupling reaction between Katritzky salts and aromatic amides. This work provides examples of the synthesis of various ketones from alkylpyridinium salts, including both primary and secondary alkylamines. Given its mild reaction conditions and high functional group tolerance, this cross-coupling strategy is expected to be useful for late-stage functionalization of
Mg(OMe)<sub>2</sub> promoted allylic isomerization of γ-hydroxy-α,β-alkenoic esters to synthesize γ-ketone esters
作者:Luhao Lai、A-Ni Li、Jiawei Zhou、Yarong Guo、Li Lin、Wei Chen、Rui Wang
DOI:10.1039/c7ob00131b
日期:——
This work concerns the Mg(OMe)2 promoted allylic isomerization of γ-hydroxy-α,β-alkenoic esters with TMEDA as an additive. The isomerization proceeded under mild conditions and afforded γ-keto esters in high yield (up to 96%) within 2 h. Both (Z)- and (E)-γ-hydroxy-α,β-alkenoic esters were tolerated under the reaction conditions. This transformation involves the in situ formation of a dienolate intermediate
Electrophilic substitution in naphthalenes: cyclisation of naphthylbutanols to tetrahydrophenanthrene
作者:Anthony H. Jackson、Patrick V. R. Shannon、Paul W. Taylor
DOI:10.1039/p29810000286
日期:——
Both 4-(1-naphthyl)butanol and 4-(2-naphthyl)butanol cyclised in refluxing boron trifluoride–ether to give 1,2,3,4-tetrahydrophenanthrene. By use of the corresponding, 1,1-dideuteriobutanol derivatives and analysis of the products by 220 MHz 1H n.m.r. spectroscopy it has been demonstrated that the 1-naphthylbutanol cyclises by two distinct pathways, (a) by direct attack (84%) at the 2-position, and
4-(1-萘基)丁醇和4-(2-萘基)丁醇均在回流的三氟化硼-醚中环化,得到1,2,3,4-四氢菲。通过使用相应的1,1-二氘代叔丁醇衍生物并通过220 MHz 1 H nmr光谱分析产物,已证明1-萘丁醇环化有两种不同的途径,(a)通过直接攻击(84%)在在第2位,以及(b)在萘核的1位通过ipso攻击(16%),然后进行重排。2-萘基丁醇仅通过在1-位上的直接取代而环化。另一方面,使用4-(4-甲氧基-1-萘基)-1,1-二氘代丁醇,ipso取代的比例上升到71%,如360 MHz所示1所得四氢菲混合物的H nmr光谱。
Photoredox‐Catalyzed Isomerization of Highly Substituted Allylic Alcohols by C−H Bond Activation
作者:Kai Guo、Zhongchao Zhang、Anding Li、Yuanhe Li、Jun Huang、Zhen Yang
DOI:10.1002/anie.202000743
日期:2020.7.6
Photoredox‐catalyzed isomerization of γ‐carbonyl‐substituted allylicalcohols to their corresponding carbonyl compounds was achieved for the first time by C−H bond activation. This catalytic redox‐neutral process resulted in the synthesis of 1,4‐dicarbonyl compounds. Notably, allylicalcohols bearing tetrasubstituted olefins can also be transformed into their corresponding carbonyl compounds. Density
作者:Imran Khan、Zhibin Luo、Yin Xu、Jimin Xie、Weihua Zhu、Bin Liu
DOI:10.1002/hlca.202000028
日期:2020.5
A direct approach to γ‐keto esters through cascade alkyne‐aldehyde reductive C−C coupling of propargyl esters and aromatic aldehydes under transition‐metal‐free (TM‐free) fashion was developed. Compared with multistep processes, this procedure provides a fast path using commercially available materials and could be handled conveniently to produce various γ‐keto esters in moderate yields.