Redstaker — A New Staking Tomato

Regioselective synthesis of diazaspiro[4.4]nona‐ and tetrazaspiro[4.5]deca‐2,9‐diene‐6‐one derivatives

“…In the course of our investigation, we have found that 3phenylmethylene-5-arylfuran-2(3H)-ones 3, are excellent building blocks for the synthesis of a variety spiropyrazole ring systems [21][22][23]. Thus, treatment of 3-phenylmethylene-5-arylfuran-2(3H)-ones 3 with nitrileimides 2a-i) generated in situ by the action of triethylamine on hydrazonoyl chlorides 1a-i [24][25][26]), in benzene under reflux, afforded the corresponding cycloadducts 5a-i in good yields (Scheme 1). The reactions of 2 with 4 are regioselective and, in each case, only one regioisomer of 5 was isolated.…”

“…Thus, treatment of 3-phenylmethylene-5-arylfuran-2(3H)-ones 3 with nitrileimides 2a-i) generated in situ by the action of triethylamine on hydrazonoyl chlorides 1a-i [24][25][26]), in benzene under reflux, afforded the corresponding cycloadducts 5a-i in good yields (Scheme 1). The reactions of 2 with 4 are regioselective and, in each case, only one regioisomer of 5 was isolated.…”