Direct Enamido C(sp<sup>2</sup>)−H Diphosphorylation Enabled by a PCET‐Triggered Double Radical Relay: Access to<i>gem</i>‐Bisphosphonates
作者:Hao‐Qiang Cao、Hao‐Nan Liu、Zhe‐Yuan Liu、Bao‐Kun Qiao、Fa‐Guang Zhang、Jun‐An Ma
DOI:10.1002/chem.202000517
日期:2020.4.24
electron-transfer (PCET)-triggered enamidoC(sp2 )-Hdiphosphorylation. This reaction represents a rare example of realizing the challenging double C-P bond formation at a single carbon atom, thus providing facile access to a broad variety of structurally diverse bisphosphonates from simple enamides under silver-mediated conditions. Initial mechanistic studies demonstrated that the diphosphorylation involves
Synthesis of diverse di- to penta-substituted 1,2-dihydropyridine derivatives from gold(I)-catalyzed intramolecular addition of tertiary enamides to alkynes
作者:Xingyi Zhang、Xin-Ming Xu、Liang Zhao、Jingsong You、Jieping Zhu、Mei-Xiang Wang
DOI:10.1016/j.tetlet.2015.04.105
日期:2015.6
alkyne-bearing tertiaryenamides underwent an efficient Au(I)-catalyzed 6-endo-dig cyclization reaction to afford a variety of di- to penta-substituted 1,2-dihydropyridine derivatives in high yields. The cyclization proceeds through a cascade comprising an intramolecular nucleophilic addition of enaminic carbon to alkyne–gold(I) complex, deprotonation, and protodeauration steps. Au(I)-catalyzed tertiary enamide–alkyne
functionalized quinolines and pyridines could be synthesized by BF3⋅OEt2‐mediated reactions of vinylazides with N‐aryl and N‐alkenyl aldimines, respectively. The reaction mechanism could be characterized as formal [4+2]‐annulation, including unprecedented enamine‐type nucleophilic attack of vinylazides to aldimines and subsequent nucleophilic cyclization onto the resulting iminodiazonium ion moieties.
Iridium-Catalyzed Enantioselective Allylation of Aryl Enamides and Enecarbamates
作者:Bei-Bei Yue、Yi Deng、Yu Zheng、Kun Wei、Yu-Rong Yang
DOI:10.1021/acs.orglett.9b00764
日期:2019.4.5
Aromatic enamide and enecarbamate as a novel type of nucleophile in the asymmetric allylation of branched, racemic allylicalcohols to give homoallylic ketones has been described. Enabled by Carreira’s chiral Ir (P, olefin) complex, the reactions proceed in good yields with excellent enantioselectivities.
A Facile and Efficient Approach to
<i>N</i>
‐Protected‐β‐Sulfinyl‐ enamines
<i>via C</i>
‐Sulfinylation of Enamides and Enecarbamates
作者:Yinhui Li、Ke Cheng、Xiaoxia Lu、Jian Sun
DOI:10.1002/adsc.201000084
日期:2010.10.9
A practical method has been developed for the C-sulfinylation of enamides and enecarbamates using sodium phenylsulfinate/methyltrichlorosilane (PhSO2Na/MeSiCl3) as the sulfinylating reagent and N,N-dimethylacetamide (DMAc) as the Lewis base promoter, which allows for the preparation of a variety of N-protected-β-sulfinylenamines in high yields and good stereoselectivities. The Lewis base is found to
已开发出一种实用的方法,使用苯磺酸钠/甲基三氯硅烷(PhSO 2 Na / MeSiCl 3)作为亚磺酰化试剂,并使用N,N-二甲基乙酰胺(DMAc)作为路易斯碱促进剂,对酰胺和烯氨基甲酸酯进行C-亚磺酰基化。以高收率和良好的立体选择性制备各种N-保护的β-亚磺酰亚胺胺。发现路易斯碱对于活性亚磺酰基化物质(PhSOC1)的原位生成和亚磺酰基化步骤均是重要的。