cetyltrimethylammonium bromide in catalyzing C–N bond formation has been studied with respect to N-alkylations of benzotriazole (Bt). Alkylations with various alkylating agents and the addition of Bt across activateddoublebonds in the Michael fashion occurred successfully in fair-to-good yields in the aqueous micellar regime. These reactions provided a mixture of N-1 and N-2 alkylated products, with a marked preference
Rhodium(<scp>iii</scp>)-catalyzed regioselective distal <i>ortho</i> C–H alkenylation of <i>N</i>-benzyl/furanylmethylpyrazoles directed by <i>N</i>-coordinating heterocycles
作者:Hyewon Kim、Raju S. Thombal、Hari Datta Khanal、Yong Rok Lee
DOI:10.1039/c9cc06758b
日期:——
C–H activation of challenging N-benzylpyrazoles was accomplished by employing rhodium(III) catalysis. This C–H activation reaction proceeds via a six-membered rhodacycle intermediate and enables distal regioselective alkenyl-functionalization on the aromaticring of N-benzylpyrazoles without the formation of bis-adducts. High functional group tolerance, low catalyst loading, and superior reactivity
具有挑战性的N-苄基吡唑类化合物的C–H活化是通过铑(III)催化完成的。这种C–H活化反应是通过六元的Rhodacycle中间体进行的,可在N-苄基吡唑的芳香环上进行远端区域选择性烯基官能化,而不会形成双加合物。该方案的一些吸引人的特征是高官能团耐受性,低催化剂负载量和烯烃部分对N-苄基吡唑的优异反应性。该方案为吲唑,苯并[ d ] [1,2,3]三唑和1-(呋喃-3-基甲基)-1 H的区域选择性官能化提供了广阔的范围。-吡唑产率高。
A Simple, Versatile Synthetic Route to<i>N</i>-1-Aryl-, -Heteroaryl-, - Acylmethyl-, -Carboxymethyl-and -Alkyl-benzotriazoles via Regiospecific or Highly Regioselective Substitutions of Benzotriazole
作者:Alan R. Katritzky、Jing Wu
DOI:10.1055/s-1994-25530
日期:——
In the absence of any added base in refluxing benzene or toluene, benzotriazole replaces the halogen atom of an α-halogenated ketone or a carboxylic ester to give the corresponding N-1-substituted benzotriazole as the only isomer. 2-Bromopyridine and 1-chloro-2,4-dinitrobenzene reacted similarly with benzotriazole to afford the corresponding N-1-substituted benzotriazole derivatives in quantitative yields. Alkyl halides reacted regioselectively to afford the N-1-alkylbenzotriazoles in ratios of more than 10 to 1 over the N-2 isomers. An α-(benzotriazol-1-yl)carboxylic ester was hydrolyzed into the corresponding carboxylic acid, which upon heating under-went smooth decarboxylation into the corresponding 1-alkylbenzotriazole.
Mitsunobu Reaction of 1,2,3-NH-Triazoles: A Regio- and Stereoselective Approach to Functionalized Triazole Derivatives
作者:Wuming Yan、Tao Liao、Odbadrakh Tuguldur、Cheng Zhong、Jeffrey L. Petersen、Xiaodong Shi
DOI:10.1002/asia.201100357
日期:2011.10.4
The Mitsunobureaction was used in the preparation of chiral triazole derivatives. The reactions gave good to excellent yields with large substrate scope. Complete stereochemistry inversion was obtained, making this strategy one practical approach for the synthesis of enantiomeric enriched triazole analogous.
<i>N</i>-Alkylation of Pyrrole, Indole, and Several Other Nitrogen Heterocycles Using Potassium Hydroxide as a Base in the Presence of Polyethylene Glycols or Their Dialkyl Ethers
作者:Kazuaki Sukata
DOI:10.1246/bcsj.56.280
日期:1983.1
The alkylation of pyrrole and indole in aqueous potassium hydroxide-organic two-phase systems in the presence of polyethylene glycols (PEG) or their dialkyl ethers (PEG-ether) as phase transfer catalysts (PTC) gave substantial quantities of the C-alkylated and C,N-polyalkylated products as well as the N-alkylated products. This fact is similar to that obtained in the presence of quaternary ammonium