Catalytic Enantioselective Reaction of α‐Aminoacetonitriles Using Chiral Bis(imidazoline) Palladium Catalysts

Abstract

The catalytic enantioselective reaction of diphenylmethylidene-protected a-aminoacetonitriles with imines has been developed. Good yields and diastereo-and enantioselectivities were observed for the reaction of various imines using chiral bis(imidazoline)/Pd catalysts.The reaction of a-aminonitriles with di-tert-butyl azodicarboxylate afforded chiral a,adiaminonitriles in high yields with high enantioselectivities.

Catalytic Conversion of Nitriles by Metal Pincer Complexes

“…Scheme 34 Enantioselective Michael addition of 2-methyl-cyanoacetate catalysed by chiral pincer complexes Scheme 35 Enantioselective Michael reaction of 2-methyl-cyanoacetate and MVK catalysed by a chiral palladium pincer complex Catalytic Conversion of Nitriles by Metal Pincer Complexes cyanoacetic acid (up to 82% yield, 90% ee) [66], α-phenylthioacetonitriles [up to 99% yield, 95:5 dr (anti/syn), 99% ee (anti)] [67], α-aminoacetonitriles [up to 95% yield, 97:3 dr (syn/anti), 99% ee (syn)] [68], dichloroacetonitrile (up to 99% yield, 94% ee) [69] and allenylnitriles (up to 89% yield, 99% ee) [70]. Whereas these transformations are all Mannich-type reactions, the same catalyst has also been used for an aza-Morita-Baylis-Hillman reaction between acrylonitrile and tosylated imines (for the product, see Scheme 37, upper right).…”

Recent Advances in the Synthesis of Hydantoins: The State of the Art of a Valuable Scaffold

“…Kondo et al recently developed an enantioselective synthesis of α,β-diaminoacetonitriles, which they used in the Bucherer−Bergs reaction without loss of enantiopurity. 34 Improvements in terms of reaction times, yields, and environmentally friendly conditions were also described. A catalyzed Bucherer−Bergs reaction was reported, in which Fe 3 O 4 nanoparticles were employed as a reusable (up to four times) Lewis acid to promote both the amino nitrile formation and the carbon dioxide addition steps.…”

Synthesis of chiral anti-1,2-diamine derivatives through copper(I)-catalyzed asymmetric α-addition of ketimines to aldimines

“…Usually, a second functional group such as ester 17 – 21 , nitrile 22 , 23 , or phosphate 18 , 24 was required to stabilize the 2-azaallyl anion (R 1 = CO 2 R, CN, or P(O)(OR) 2 ). Furthermore, the introduction of a strong electron-withdrawing group on the α-position of ketimine would lower p K a value of the α-protons and thus enable a facile proton-transfer α-addition to aldimines, which would produce chiral 1,2-diamine derivatives in the presence of a chiral catalyst.…”