(5aS,10bR)-5a,10b-dihydro-2-(2,4,6-trimethylphenyl)-4H,6H-indeno[2,1-b]-1,2,4-triazolo[4,3-d]-1,4-oxazinium chloride; triethylamine in ethyl acetate T=80°C; 4 h; Inert atmosphereMolecular sieve;