Pd(II)-Catalyzed Aerobic Intermolecular 1,2-Diamination of Conjugated Dienes: A Regio- and Chemoselective [4 + 2] Annulation for the Synthesis of Tetrahydroquinoxalines
作者:Zhengxing Wu、Ke Wen、Jingang Zhang、Wanbin Zhang
DOI:10.1021/acs.orglett.7b00919
日期:2017.6.2
A Pd(II)-catalyzed aerobic intermolecular 1,2-diamination of conjugateddienes was developed for the regio- and chemoselective preparation of a variety of functionalized tetrahydroquinoxalines, using simple sulfonyl protected o-phenylendiamines as a nitrogen source. This methodology provides a direct and efficient synthesis of tetrahydroquinoxalines. O2 was used as the stoichiometric oxidant, and reaction
achieve radical boryl substitutions of a variety of alkyl radical precursors. Dehalogenative, deaminative, decharcogenative, and decarboxylative borylations proceeded in the presence of a radical initiator to give the corresponding organic boron compounds. Radical clock experiments and computational studies have provided insights into the mechanism of the homolytic substitution (SH2) of the borylstannanes
(o -Phenylenediamino)borylstannanes是新合成的,可实现多种烷基自由基前体的自由基硼基取代。在自由基引发剂的存在下进行脱卤,脱氨基,脱碳和脱羧基的硼化反应,得到相应的有机硼化合物。自由基时钟实验和计算研究提供了对硼烷基锡烷被烷基中间体中间体均质取代(S H 2)的机理的见解。DFT计算表明,苯二胺基结构降低了LUMO能级,包括硼原子上的空位p-轨道,从而增强了对S H 2中烷基的反应性。此外,C(sp 3使用x吨酮的三重态完成THF的H-硼化反应。
A formal [4 + 2] annulation of diamines and prop-2-ynyl sulfonium salts for the synthesis of tetrahydroquinoxalines
A formal [4 + 2] annulation of diamines and prop-2-ynyl sulfonium salts was developed. This strategy enables efficient access to tetrahydroquinoxalines in excellent yields.
Bissulfonamide derivatives of formula (I) are capable of inhibiting: a) the biosynthesis of aromatic amino acids via the shikimate pathway and b) the catabolism of quinic acid, wherein: Ar is an aryl or heteroaryl group; R1 and R2 are the same or different and each represent hydrogen or alkyl or R1 and R2 together form a C1-C3 alkylene group, -CO- or -CS-; and R3 and R4 are the same or different and each represent -alkyl-aryl, -alkyl-heteroaryl, -alkenyl-aryl, -alkenyl-heteroaryl, -alkynyl-aryl-alkynyl-heterorayl, aryl or heteroaryl.