Novel preparation of non-racemic 1-[α-(1-azacycloalkyl)benzyl]-2-naphthols from Betti base and their application as chiral ligands in the asymmetric addition of diethylzinc to aryl aldehydes
Redox-Neutral α-Oxygenation of Amines: Reaction Development and Elucidation of the Mechanism
作者:Matthew T. Richers、Martin Breugst、Alena Yu. Platonova、Anja Ullrich、Arne Dieckmann、K. N. Houk、Daniel Seidel
DOI:10.1021/ja501988b
日期:2014.4.23
secondary amines and 2-hydroxybenzaldehydes or related ketones react to furnish benzo[e][1,3]oxazine structures in generally good yields. This overall redox-neutral amine α-C–H functionalization features a combined reductive N-alkylation/oxidative α-functionalization and is catalyzed by acetic acid. In contrast to previous reports, no external oxidants or metal catalysts are required. Reactions performed
Divergent reaction: metal & oxidant free direct C–H aryloxylation and hydride free formal reductive N-benzylation of N-heterocycles
作者:Sujit Mahato、Md Ashraful Haque、Soumita Dwari、Chandan K. Jana
DOI:10.1039/c4ra05045b
日期:——
Metal, oxidant and other additive-free novel methods for direct C–H aryloxylation of aliphatic amines are developed. In the presence of excess amine, the course of the reaction was diverted, producing various arylmethylamines via hydride-free formal reductive amination. Involvement of a quinonemethideintermediate was revealed from mechanistic studies.
Synthesis of chiral ligands derived from the Betti base and their use in the enantioselective addition of diethylzinc to aromatic aldehydes
作者:Jun Lu、Xuenong Xu、Cunde Wang、Jiangang He、Yuefei Hu、Hongwen Hu
DOI:10.1016/s0040-4039(02)01985-8
日期:2002.11
A novel procedure for selective direct N,N-alkylation of the chiral Betti base was developed, and a new family of chiralligands, (S)-1-(α-cycloaminobenzyl)-2-naphthols, were prepared. The ligands with five- and six-membered cyclic amines showed highly efficient asymmetric induction in the addition of diethylzinc to aromaticaldehydes in 93–96% yields and 91–99% ee.
Iterative direct C<sub>(sp3)</sub>–H functionalization of amines: diastereoselective divergent syntheses of α,α′-disubstituted alicyclic amines
作者:Sujit Mahato、Chandan K. Jana
DOI:10.1039/c6ob02257j
日期:——
A novel iterative C(sp3)–H oxygenation/C–C bond formation strategy, which avoids repetitive N-protection/-deprotection steps, was developed for direct α,α′-difunctionalization of alicyclic amines. The method is highly efficient and stereoselective in producing syn-α,α′-disubstituted aliphatic N-heterocycles. Synthetic potential and practicability of the method was demonstrated by an easy and straightforward