The Reaction of Cyclopentanone with Cyanomethylene Reagents: Novel Synthesis of Pyrazole, Thiophene, and Pyridazine Derivatives

Table 1

Physical and microanalysis of the newly synthesized compounds 3a–16b.

Comp. no.	m.p.	Yield (%)	Solvent of crystallization	Molecular formulae	C%	H%	N%	S%
3a	148–150	78	Ethanol	C8H8N2; 132.16	72.70	6.10	21.20
3b	100–112	81	Ethanol	C10H13NO2; 179.22	67.12	7.21	7.79
5a	98–100	78	Ethanol	C14H12N4; 236.27	71.02	5.22	12.59
5b	60–62	86	Ethanol	C14H11ClN4; 270.72	62.08	4.39	20.93
5c	88–90	90	Ethanol	C16H17N3O2 283.33	67.66	5.93	14.95
5d	58–60	77	Ethanol	C16H16ClN3O2; 317.77	60.38	5.11	13.08
7a	70–72	78	Ethanol	C14H18N6; 270.33	62.36	6.83	31.11
7b	80–82	82	Ethanol	C20H22N6; 346.43	69.63	6.55	24.07
7c	68–70	78	Ethanol	C14H17N5O; 271.32	61.77	6.49	25.64
7d	78–80	80	Ethanol	C20H21N5O; 347.41	69.25	6.27	19.84
9a	98–100	78	Ethanol	C15H12N2; 220.27	81.67	5.33	12.57
9b	40–42	70	Ethanol	C17H17NO2; 267.32	76.51	6.58	5.33
11a	98–100	82	Ethanol	C17H13N3; 259.31	78.63	4.93	16.08
11b	80–82	82	Ethanol	C19H18N2O2; 306.14	74.62	5.86	9.08
11c	68–70	82	Ethanol	C19H18N2O2; 306.14	74.52	5.72	9.22
11d	58–60	77	Ethanol	C21H23NO4; 353.41	71.58	6.62	4.25
13a	88–90	80	Ethanol	C8H8N2S; 164.23	58.51	4.91	17.06	19.52
13b	70–72	72	Ethanol	C10H13NO2S; 211.28	58.85	6.20	6.63	15.18
14a	120–122	86	Ethanol	C14H12N4S; 268.34	62.74	4.75	20.67	12.28
14b	78–81	69	Ethanol	C16H17N3O2S; 315.39	61.31	5.67	13.15	10.06
15a	90–92	72	1,4-dioxane	C16H14N4OS; 310.37	62.03	4.74	17.99	10.48
15b	68–70	83	1,4-dioxane	C18H19N3O3S; 357.43	60.58	5.52	11.84	9.32
16a	78–80	80	1,4-dioxane	C14H12N4; 236.27	71.27	4.92	23.88
16b	70–72	77	1,4-dioxane	C14H11N3O; 237.26	70.64	4.83	17.93