TY - JOUR

T1 - 2-Azidoazirines suitable for click chemistry: synthesis of 1-(2H-azirin-2-yl)-1H-1,2,3-triazoles

AU - Голубев, Артём Алексеевич

AU - Сметанин, Илья Алексеевич

AU - Симдянов, Иван Владимирович

AU - Агафонова, Анастасия Викторовна

AU - Ростовский, Николай Витальевич

AU - Хлебников, Александр Феодосиевич

AU - Новиков, Михаил Сергеевич

PY - 2024/11/11

Y1 - 2024/11/11

N2 - 2-Azidoazirines, sufficiently stable to be isolated in good yields, were synthesized by the cascade SN2'-SN2' substitution of bromine in methyl 2-bromo-2H-azirine-2-carboxylates using sodium azide in acetonitrile. According to the DFT calculations, the first step, Br/N3 exchange, is rate-determining and occurs in a concerted manner, while the subsequent N3/N3 exchange is a stepwise process. An alternative method using the TMSN3/Et3N/CH2Cl2 system permits the isolation in pure form of only 2-azidoazirines having ortho-substituted aryl substituent at C3, although it is more efficient in a one-pot synthesis of 1-(azirin-2-yl)-1,2,3-triazoles from the bromoazirines via the “cascade SN2'-SN2' substitution/CuAAC reaction” sequence. The protocol has a broad scope for both azirines and alkynes and provides good product yields. The described CuAAC reaction of 2-azidoazirines represents the first example of a copper(I)-catalyzed reaction of azirines that occurs with the preservation of the azirine ring.

AB - 2-Azidoazirines, sufficiently stable to be isolated in good yields, were synthesized by the cascade SN2'-SN2' substitution of bromine in methyl 2-bromo-2H-azirine-2-carboxylates using sodium azide in acetonitrile. According to the DFT calculations, the first step, Br/N3 exchange, is rate-determining and occurs in a concerted manner, while the subsequent N3/N3 exchange is a stepwise process. An alternative method using the TMSN3/Et3N/CH2Cl2 system permits the isolation in pure form of only 2-azidoazirines having ortho-substituted aryl substituent at C3, although it is more efficient in a one-pot synthesis of 1-(azirin-2-yl)-1,2,3-triazoles from the bromoazirines via the “cascade SN2'-SN2' substitution/CuAAC reaction” sequence. The protocol has a broad scope for both azirines and alkynes and provides good product yields. The described CuAAC reaction of 2-azidoazirines represents the first example of a copper(I)-catalyzed reaction of azirines that occurs with the preservation of the azirine ring.

UR - https://www.mendeley.com/catalogue/3d98f5c5-f2f0-3a09-8a0d-9ee7d16d3cda/

U2 - 10.1039/d4nj03517h

DO - 10.1039/d4nj03517h

M3 - Article

VL - 48

SP - 19957

EP - 19962

JO - New Journal of Chemistry

JF - New Journal of Chemistry

SN - 1144-0546

IS - 47

ER -