Sulfuric Acid → trans-5-Methyl-3-p-cyanostyryl-1,2,4-oxadiazole

Participants

Reaction Steps

A solution of sodium nitrite (0.80g) in water (3 ml) was added during 20 min. to a stirred suspension of trans-5-methyl-3-p-aminostyryl-1,2,4-oxadiazole (2.01g) in 2N-sulphuric acid (20 ml) at 5°. The solution was maintained at 10° for one hour and then added during 30 min. to a solution of cuprous cyanide (1.01g) and potassium cyanide (2.28g) in water (8 ml) at 35°. The mixture was then heated to 70° when nitrogen ceased to be evolved. The cooled reaction mixture was filtered and the solid was washed with water and dried. The solid was triturated with boiling chloroform (150 ml) and the chloroform solution was evaporated under reduced pressure to give an orange solid which was recrystallised from ethanol (15 ml) with charcoal decolourisation to give title compound 0.62g (29.5%), m.p. 162°-163°, λmax. (EtOH) 288 nm, ε 32,300, νmax (CHBr3) 2250, (CN) 972 cm.-1 (trans CH=CH), τ (CDCl3) values include 2.27 and 2.87 (AB quartet, J = 16; trans CH=CH) and 7.36 (CH3).

Provenance & Evidence