Synthesis of chiral pyridine-oxazolines via a catalytic asymmetric Heine reaction of meso-N-(2-picolinoyl)-aziridines

Abstract

An asymmetric Heine reaction of (meso)-N-(2-picolinoyl)-aziridines catalyzed by a chiral ytterbium(III)–N,N’-dioxide complex was established. A novel library of pyridine-oxazolines was obtained in decent yields and enantioselectivities, which show potential as...

Synthesis of N–H Aziridines from Unactivated Olefins Using Hydroxylamine-O-Sulfonic Acids as Aminating Agent

“…20 Additionally, 2 can also undergo condensation with picolinic acid, followed by cyclization under the NaI/acetone conditions (Heine reaction) to form oxazole compound 41 in 73% total yield (Scheme 4b). 21 Furthermore, 2 can not only engage in Chan-Lam-Evans coupling with arylboronic acid compounds under copper catalysis but also react with vinyl bromides under palladium catalysis via Buchwald-Hartwig coupling (Scheme 4c, d) to produce 42 and 43 in 60% and 52% yield, respectively. 22,23…”

Synthesis of N–H Aziridines from Unactivated Olefins Using Hydroxylamine-O-Sulfonic Acids as Aminating Agent

“…21 Additionally, 2 can also undergo condensation with picolinic acid, followed by cyclization under the NaI/acetone conditions (Heine reaction) to form oxazole compound 41 in 73% total yield (Scheme 4b). 22 Furthermore, 2 can not only engage in Chan−Lam− Evans coupling with arylboronic acid compounds under copper catalysis but also react with vinyl bromides under palladium catalysis via Buchwald−Hartwig coupling (Scheme 4c,d) to produce 42 and 43 in 60% and 52% yield, respectively. 23,24 We tentatively propose a plausible mechanism for this aziridiantion (Scheme 5).…”

“…As shown in Scheme , aziridine 2 can undergo nucleophilic ring-opening reactions with nucleophilic reagents like p -toluenethiol to yield cyclooctamine 40 in 71% yield (Scheme a) . Additionally, 2 can also undergo condensation with picolinic acid, followed by cyclization under the NaI/acetone conditions (Heine reaction) to form oxazole compound 41 in 73% total yield (Scheme b) . Furthermore, 2 can not only engage in Chan–Lam–Evans coupling with arylboronic acid compounds under copper catalysis but also react with vinyl bromides under palladium catalysis via Buchwald–Hartwig coupling (Scheme c,d) to produce 42 and 43 in 60% and 52% yield, respectively. , …”

Recent advances in the accessibility, synthetic utility, and biological applications of aziridines

“…The reaction proceeds via an asymmetric Heine reaction, giving excellent yields with very good enantioselectivities (Scheme 52). 84…”