Asymmetric synthesis of 2H-azirines derived from phosphine oxides using solid-supported amines. Ring opening of azirines with carboxylic acids.
A simple and efficient asymmetric synthesis of 2H-azirine-2-phosphine oxides 3 is described. The key step is a solid-phase bound achiral or chiral amine-mediated Neber reaction of beta-ketoxime tosylates derived from phosphine oxides 1. Reaction of 2H-azirines 3 and 11 with carboxylic acids 4 gives phosphorylated ketamides 5 and 12. Ring closure of ketamides 5 and 12 with triphenylphosphine and hexachloroethane in the presence of triethylamine leads to the formation of phosphorylated oxazoles 8 and 13.
Palacios
Francisco
F
Departamento de Química Orgánica I, Facultad de Farmacia, Universidad del País Vasco, Apartado 450, 01080 Vitoria, Spain. qoppagaf@vf.ehu.es
Aparicio
Domitila
D
Ochoa De Retana
Ana María
AM
de los Santos
Jesús M
JM
Gil
José Ignacio
JI
Alonso
José María
JM
D000588:Amines / Q000737:chemistry*; D001389:Azirines / Q000138:chemical synthesis* / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D007202:Indicators and Reagents; D010720:Phosphines / Q000737:chemistry*; D013329:Structure-Activity Relationship
D000588:Amines; D001389:Azirines; D002264:Carboxylic Acids; D007202:Indicators and Reagents; D010720:Phosphines