Synthesis of indoles, benzofurans, and related heterocycles via an acetylene-activated S<sub>N</sub>Ar/intramolecular cyclization cascade sequence in water or DMSO
作者:R. Hudson、N. P. Bizier、K. N. Esdale、J. L. Katz
DOI:10.1039/c4ob02549k
日期:——
The synthesis of 2-substituted indoles and benzofurans was achieved by nucleophilic aromatic substitution, followed by subsequent 5-endo-dig cyclization between the nucleophile and an ortho acetylene. The acetylene serves the dual role of the electron withdrawing group to activate the substrate for SNAr, and the C1–C2 carbon scaffold for the newly formed 5-membered heteroaromatic ring. This method
2-取代的吲哚和苯并呋喃的合成是通过亲核芳族取代,随后在亲核体和邻乙炔之间进行5-endo-dig环化来实现的。乙炔起着吸电子基团的双重作用,以激活S N Ar的底物,而C1-C2碳骨架则用于新形成的5元杂芳族环。这种方法可以使Ar–X–N / O–C1的键形成顺序在一个合成步骤中进行,从而以中等至高收率提供吲哚和苯并呋喃。由于该方法不是过渡金属介导的,因此可以耐受溴化和氯化的底物,可以使用水或水-DMSO混合物作为溶剂进行苯并呋喃的形成。
A Domino Protocol toward High‐performance Unsymmetrical Dibenzo[d,d′]thieno[2,3‐b;4,5‐b′]dithiophenes Semiconductors
A trisulfur radical anion (S3.−) triggered domino thienannulation strategy for the synthesis of dibenzo[d,d′]thieno[2,3-b;4,5-b′]dithiophenes (DBTDTs) has been developed. This domino protocol is featured by no metal catalyst and the formation of six C−S and one C−C bonds in one-pot reaction. A plausible mechanism has been proposed by control experiments, intermediate trapping experiments, etc. The
开发了一种三硫自由基阴离子(S 3 .− )触发的多米诺噻吩环化策略,用于合成二苯并[ d,d' ]噻吩并[2,3- b ;4,5- b ']二噻吩(DBTDT)。该多米诺骨牌协议的特点是无需金属催化剂,在一锅反应中形成六个 C−S 和一个 C−C 键。通过控制实验、中间捕获实验等提出了一种合理的机制。DBTDT独特的不对称结构赋予其人字形堆积结构和分子间弱的S⋅⋅⋅S相互作用以及高转移积分,从而实现高载流子有机场效应晶体管的迁移率为1.52 cm 2 V -1 s -1 。
A concise synthesis of chiral indanes as α 1A adrenoceptor partial agonists
作者:Lee R. Roberts、Matthew S. Corbett、Steven J. Fussell、Laure Hitzel、Alan S. Jessiman、Helen J. Mason、Rachel Osborne、Michael J. Ralph、Adam S.D. Stennett、Simon Wheeler、R. Ian Storer
DOI:10.1016/j.tetlet.2015.10.004
日期:2015.11
The synthesis of a series of chiral indanes with reported am partial agonist activity is outlined, applying a rhodium catalysed cyclisation for template construction. This method was extended to the asymmetric synthesis of lead compound PF-03774076 (1) which was prepared on >20 g scale in seven steps. Highlights include Rh-mediated cyclocarbonylation and an asymmetric alkene hydrogenation. (C) 2015 Elsevier Ltd. All rights reserved.
Sakamoto, Takao; Kondo, Yoshinori; Watanabe, Ryo, Chemical and pharmaceutical bulletin, 1986, vol. 34, # 7, p. 2719 - 2724