Catalytic asymmetric addition reactions leading to carbon-carbon bond formation: Phenyl and alkenyl transfer to aldehydes and alkynylation of α-imino esters

Abstract

Optically active tertiary aminonaphthol ligands were obtained by a new, convenient procedure and were found to catalyze the enantioselective alkenyl and phenyl transfer to aldehydes in high yields and excellent enantiomeric excesses (ee's). The catalytic asymmetric introduction of alkynyl functionality to α-amino acid derivatives was realized by the direct addition of terminal alkynes to α-imino ester in the presence of chiral copper(I) complex under mild reaction conditions.

Palladium‐Catalyzed Hydroalkynylation of Alkylidenecyclopropanes

“…[3,4] Catalysts able to promote hydroalkynylations of unsaturated molecules other than alkynes are still quite rare. [5][6][7][8][9][10] Usually, in these cases, very reactive C À C double bonds such as those of allenes, enones, or strained cyclic alkenes are required. [5][6][7] Indeed, the first examples involving less reactive alkenes have only been reported very recently, and were achieved by using Ni catalysts.…”

The inexpensive additive N‐methylmorpholine effectively decreases the equivalents of nucleophiles in the catalytic highly enantioselective arylation of aryl aldehydes

“…[1][2][3][4][5][6][7][8] Accordingly, the catalytic asymmetric addition of arylmetal reagents and aryl boronic acids to aldehydes has attracted considerable attention over the past decades. [9][10][11][12][13][14][15][16][17] Since Fu and coworkers seminally reported the asymmetric addition with Ph 2 Zn, 18 arylzinc reagents from various aryl sources such as arylboronic acids have been commonly explored for the enantioselective synthesis of diarylmethanols. [19][20][21][22][23][24][25][26][27][28][29][30] Meanwhile, other active aryl metals such as arylaluminum, arylmagnesium, and aryllithium have transferred aryl to less active aryl titanium intermediates ArTi(Oi-Pr) 3 as nucleophiles for enantiopure diarylmethanols because of their higher reactivity.…”

“…Enantiopure diarylmethanols are important structural scaffolds in the synthesis of pharmaceuticals and bioactive compounds . Accordingly, the catalytic asymmetric addition of arylmetal reagents and aryl boronic acids to aldehydes has attracted considerable attention over the past decades . Since Fu and coworkers seminally reported the asymmetric addition with Ph 2 Zn, arylzinc reagents from various aryl sources such as arylboronic acids have been commonly explored for the enantioselective synthesis of diarylmethanols .…”