A Simplified Protocol for the Stereospecific Nickel-Catalyzed C–S Vinylation Using NiX2 Salts and Alkyl Phosphites
作者:Austin D. Marchese、Bijan Mirabi、Egor M. Larin、Mark Lautens
DOI:10.1055/s-0039-1690717
日期:2020.1
A Ni-catalyzed C–S cross-coupling using only NiI2 (0.5–2.5 mol%) and P(OiPr)3 (2.0–10.0 mol%) is reported. Using an air-stable Ni(II) precatalyst, and a cheap and commercially available ligand, a scalable and robust method was developed to cross-couple various thiophenols and styryl bromides, including some sterically encumbered thiols, an α-bromocinnamaldehyde as well as a thiolation-cyclization.
据报道,仅使用NiI 2(0.5–2.5 mol%)和P(O i Pr)3(2.0–10.0 mol%)的Ni催化的C–S交叉偶联。使用空气稳定的Ni(II)预催化剂和便宜的市售配体,开发了一种可扩展且稳健的方法来交叉偶联各种硫酚和苯乙烯基溴化物,包括一些空间受限的硫醇,α-溴肉桂醛和硫醇化环化。
Silver-catalyzed Double Decarboxylative Radical Alkynylation/Annulation of Arylpropiolic Acids with α-keto Acids: Access to Ynones and Flavones under Mild Conditions
Ynones are privileged buildingblocks in various organic syntheses of heterocyclicderivatives due to their multifunctional nature, and flavones are an important class of natural products with a wide range of biological activities. We describe the catalytic double decarboxylative alkynylation of arylpropiolic acids with α‐keto acids. With Ag(I)/persulfate as the catalysis system, the valuable ynones
Phosphine-mediated partial reduction of alkynes to form both (<i>E</i>)- and (<i>Z</i>)-alkenes
作者:Brett M. Pierce、Brittany F. Simpson、Kane H. Ferguson、Rachel E. Whittaker
DOI:10.1039/c8ob01848k
日期:——
phosphine-mediated partial reduction of alkynyl carbonyls to the corresponding alkenes was developed. Tuning of the reaction conditions led to either the (E)- or (Z)-diastereomer with high selectivity. A range of alkynyl esters, amides, and ketones were reduced to form alkenes in good to high yields and with excellent functional group tolerance.
N-Alkynylated sulfoximines have been obtained by copper-catalyzed cross-coupling reactions starting from NH-sulfoximines and bromoacetylenes in moderate to good yields. The reaction conditions are mild, and the substrate scope is wide.