我们开发了一种灵活的方法,能够在 BF 3 ⋅ Et 2 O 的存在下,在钯或铜催化下获得高度官能化的吡咯。这种催化方法利用市售胺作为反应伙伴,具有广泛的范围、可扩展和友好的操作仅产生水作为副产品。该协议的普遍性通过一系列二、三、四和五取代吡咯的成功制备得到证明。该方法适用于生物活性化合物的合成和衍生化。
decades of development, carbonylation reactions have become one of the most powerful tools in modern organic synthesis. However, the requirement of CO gas limits the applications of such reactions. Reported herein is a versatile and practical protocol for carbonylativereactions which rely on the cooperation of phenyl formate and nonaflate, and the generation of CO in situ. This protocol has a high functional‐group
Sunlight-Driven Decarboxylative Alkynylation of α-Keto Acids with Bromoacetylenes by Hypervalent Iodine Reagent Catalysis: A Facile Approach to Ynones
作者:Hui Tan、Hongji Li、Wangqin Ji、Lei Wang
DOI:10.1002/anie.201503479
日期:2015.7.13
A novel and practical decarboxylativealkynylation of α‐keto acids with bromoacetylenes is catalyzed by hypervalent iodine(III) reagents when irradiation by sunlight at room temperature. The product ynones are generated in good yields. Experiments show that results obtained with blue light (λ=450–455 nm) are comparable to those obtained when using sunlight. Mechanistic studies demonstrate that the
Regiocontrolled synthesis of 2,4,6-triarylpyridines from methyl ketones, electron-deficient acetylenes and ammonium acetate
作者:Dmitrii A. Shabalin、Marina Yu. Dvorko、Elena Yu. Schmidt、Boris A. Trofimov
DOI:10.1039/d1ob00193k
日期:——
A novel one-pot two-step approach for the synthesis of 2,4,6-triarylpyridines via t-BuOK/DMSO-promoted C-vinylation of a variety of methyl ketones with electron-deficient acetylenes (alkynones) followed by a cyclization of the in situ generated unsaturated 1,5-dicarbonyl species with ammonium acetate has been developed. This approach possesses competitive advantages such as high regioselectivity, available
Aryl-palladium-NHC complex: efficient phosphine-free catalyst precursors for the carbonylation of aryl iodides with amines or alkynes
作者:Chunyan Zhang、Jianhua Liu、Chungu Xia
DOI:10.1039/c4ob01878h
日期:——
aryl-palladium-NHC compounds was prepared according to the reported methods and their catalytic activity in the carbonylation of aryl iodides to synthesize α-keto amides and alkynones was examined. These practical aryl-palladium-NHC complexes have shown highly efficient catalyzed carbonylation and Sonogashira carbonylation reactions, with high turnover number in synthesis of α-keto amides (TON = 4300) and in synthesis
An acid-mediated selective cleavage of C–C doublebond of N-(2-hydroxylphenyl)enaminones with formation a new C–O bond for the synthesis of 2-substituted benzoxazoles has been developed. This protocol proceeds under transition metal- and oxidant-free conditions with broad functional group tolerance. The oxidative cleavage of C–C doublebond of N-(2-hydroxylphenyl)enaminone is also realized using NCS