Synthesis of Pyridines by Carbenoid-Mediated Ring Opening of 2<i>H</i>-Azirines
作者:Nicole S. Y. Loy、Alok Singh、Xianxiu Xu、Cheol-Min Park
DOI:10.1002/anie.201209301
日期:2013.2.18
a wide range of substituents on the resulting pyridinering using mild reaction conditions (see scheme; esp=α,α,α′,α′‐tetramethyl‐1,3‐benzenedipropionic acid). The formation of the key intermediate is catalyst‐controlled, and subsequent cyclization and oxidation affords pyridines in excellent yields. The method has been used for the efficient synthesis of polyarylpyridines.
Pyrolysis and photolysis of 1-aroylamino-4,5-diaryl-1,2,3-triazoles: Generation and thermal transformations of 4,5-diaryl-1,2,3-triazolyl radicals
作者:C. P. Hadjiantoniou-Maroulis、A. Ph. Charalambopoulos、A. J. Maroulis
DOI:10.1002/jhet.5570350418
日期:1998.7
The pyrolysis of 1-aroylamino-4,5-diphenyl-1,2,3-triazoles 1 yields, pressumably via the 4,5-diphenyl-1,2,3-triazolyl radical (2a), 2,3-diphenyl-2H-azirine (11a) and 2-aryl-4,5-diphenylimidazoles 14 as the major products. Upon irradiation 1-benzoylamino-4,5-diphenyl-1,2,3-triazole (1a) gives 4,5-diphenyl-1 (2)H-1,2,3-triazole (4a) via the 1,2,3-triazolyl radical 2a, together with benzamide (5a) and
Rh(<scp>ii</scp>)-catalyzed cycloadditions of 1-tosyl 1,2,3-triazoles with 2H-azirines: switchable reactivity of Rh-azavinylcarbene as [2C]- or aza-[3C]-synthon
作者:Yuanhao Wang、Xiaoqiang Lei、Yefeng Tang
DOI:10.1039/c5cc00268k
日期:——
The Rh(II)-catalyzed formal [3+2] and [3+3] cycloadditions of 1-tosyl 1,2,3-triazoles with 2H-azirines have been developed, which enable the efficient synthesis of polysubstituted 3-aminopyrroles and 1,2-dihydropyrazines, respectively. The reported [3+2] cycloaddition represents the first application of 1-sulfonyl 1,2,3-triazole as a [2C]-component in relevant cycloaddition reactions.
A novel and efficient iron-catalyzed cycloaddition reaction using readily available 2,3-diaryl-2H-azirines and primary amides is reported. A wide range of trisubstituted oxazoles could be achieved in good yields with good functional group compatibility. In this transformation, two C–N bonds were cleaed and new C–N and C–O bonds were formed.
Rhodium-catalysed synthesis of fused pyrimidine derivatives employing N-sulfonyl-1,2,3-triazoles as a 1-aza-[4C] synthon
作者:Ze-Feng Xu、Yuehui An、Yidian Chen、Shengguo Duan
DOI:10.1016/j.tetlet.2019.06.023
日期:2019.7
A new synthetic application of N-sulfonyl-1,2,3-triazoles acting as a 1-aza-[4C] synthon via the 1,2-shift reaction of an α-imine rhodium carbene was developed for the synthesis of fused pyrimidine derivatives. The high reactivity of the strained three-membered 2H-azirine ring facilitated the unusual cyclization of electron-deficient dienes with electron-deficient dienophiles. The compatibility was