Table 3. Synthesis of 4H-pyran and -chromene derivatives 6a–i, 7a–f and 8a–f catalyzed by Arg@ZY-Fe₃O₄ under the optimized reaction conditions^a.

Entry	R1	R2	Product	Time (min)	Yielda (%)	M.p. (°C) (lit.)	AEfb (%)/E-factor
1	Resorcinol	H	6a	5	97	238–239 (230–231)52	93.6/0.07
2	Resorcinol	4-Cl	6b	7	93	155–156 (160–162)52	93.6/0.07
3	Resorcinol	2,4-Cl	6c	9	91	252–254 (257–259)46	93.6/0.08
4	Resorcinol	2-NO2	6d	7	92	176–178 (160–162)46	93.6/0.07
5	Resorcinol	3-NO2	6e	8	95	174–176 (170–172)55	93.6/0.07
6	Resorcinol	4-NO2	6f	5	99	165–167 (168–170)46	93.6/0.07
7	Resorcinol	4-CH3	6g	12	91	188–190 (182–183)52	93.6/0.08
8	Resorcinol	4-OCH3	6h	14	90	190–192 (111–113)52	93.6/0.08
9	Resorcinol	3,4-OCH3	6i	12	88	152–154 (148–150)61	93.6/0.08
10	Dimedone	H	7a	7	95	227–229 (230–231)55	94.2/0.06
11	Dimedone	2-Cl	7b	9	93	192–194 (195–197)55	94.2/0.07
12	Dimedone	2,4-Cl	7c	10	95	192–194 (190–191)55	94.2/0.06
13	Dimedone	2-NO2	7d	7	96	241–243 (230–232)54	94.2/0.06
14	Dimedone	4-NO2	7e	5	99	190–191 (178–180)54	94.2/0.06
15	Dimedone	4-OCH3	7f	12	91	188–190 (201–203)55	94.2/0.07
16	2-Naphthol	H	8a	12	90	287–289 (281–283)61	94.3/0.07
17	2-Naphthol	2-Cl	8b	11	92	266–268 (270–271)55	94.3/0.07
18	2-Naphthol	3-NO2	8c	10	92	238–240 (238–240)55	94.3/0.07
19	2-Naphthol	4-NO2	8d	9	97	186–188 (184–185)55	94.3/0.06
20	2-Naphthol	4-OCH3	8e	14	89	171–173 (188–189)55	94.3/0.07
21	2-Naphthol	3,4-OCH3	8f	11	90	187–189 (195–196)62	94.3/0.07

^aPure product isolated.

^bAtom economy of efficiency.