N-磺酰基和N-氨磺酰基叠氮化物与末端炔烃的环加成通常通过烯酮亚胺中间体产生酰胺衍生物。我们在此描述了一种使用脯氨酰胺配体的Cu( I ) 催化方法,该方法通过抑制 5-铜三唑中间体的N 1 -N 2键的裂解,在水介质中选择性生成 N -磺酰基和氨磺酰三唑。本方法温和且耐空气、湿气和多种官能团,从而可以轻松获得各种三唑产品。
with exclusive regioselectivity and stereoselectivity. Functional application of such a resultant product by oxidative addition and epoxidation is also explored. Notably, the treatment of a pyrroline-fused N-glycoside (3a) with TMSOTf efficiently leads to an interesting unexpected C-nucleoside (9) via a TMSOTf-inducing ring opening/acetyl migration/ringclosingreaction sequence.
Sequential Functionalization of the OH and C(<i>sp</i><sup>2</sup>)O Bonds of Tropolones by Alkynes and<i>N</i>-Sulfonyl Azides
作者:Boram Seo、Woo Hyung Jeon、Chul-Eui Kim、Sanghyuck Kim、Sung Hong Kim、Phil Ho Lee
DOI:10.1002/adsc.201500829
日期:2016.3.31
Sequentialcopper‐catalyzed [3+2] cycloaddition, rhodium‐catalyzed OH insertion, intramolecular 1,8‐addition, and rearrangement starting from 1‐alkynes, N‐sulfonyl azides, and tropolones is demonstrated for the synthesis of the 2‐functionalized aminotropones in one pot. These results indicate that sequential functionalization of OH and C(sp2)O bonds smoothly occurs in the C(sp2)OH bonds of tropolone
The rhodium(II)‐catalyzed denitrogenative coupling of N‐alkylsulfonyl 1,2,3‐triazoles with 1,3,5‐trioxane led to nine‐membered‐ringed trioxazonines in moderate‐to‐good yields. 1,3,5‐Trioxane, acting as an oxygen nucleophile, reacted with the α‐aza‐vinylcarbene intermediate, giving rise to ylide formation, which was probably the key step in the reaction. Triazoles that contained aryl substituents with
An efficient room-temperature method for the synthesis of 1-sulfonyl-1,2,3-triazoles from in situgeneratedcopper(I) acetylides and sulfonyl azides is described. The copper(I) thiophene-2-carboxylate (CuTC) catalyst produces the title compounds under both nonbasic anhydrous and aqueous conditions in good yields.
Tandem O–H Insertion/[1,3]-Alkyl Shift of Rhodium Azavinyl Carbenoids with Benzylic Alcohols: A Route To Convert C–OH Bonds into C–C Bonds
作者:Pengbing Mi、Rapolu Kiran Kumar、Peiqiu Liao、Xihe Bi
DOI:10.1021/acs.orglett.6b02459
日期:2016.10.7
Alcohols are among the most abundant and commonly used organic feedstock in industrial processes and academic research. The first tandem O–H insertion/[1,3]-alkyl shift reaction reported is between benzylicalcohols and rhodium azavinyl carbenoids derived from N-sulfonyl-1,2,3-triazoles, which provides a strategically novel way of cleaving C–OH bonds and forming C–C bonds. The substrate scope is broad