Ester substituents in the cyclopropane ring of methanofullerenes in the Bingel–Hirsch reaction.

Entry	R1	R2	Yield, %	Reference
73	CH3	CH3	28	62
17	C4H9	C4H9	35
19	C8H17	C8H17	32
102	(CH2)2OCH3	(CH2)2OCH3	21
85			37
103	(CH2)11–CH3	CH3	59	49
104	(CH2)19–CH3	CH3	50
105	(CH2)2–O–CH3	C2H5	nra	63
106	CH2–CH CH2	CH2–CH CH2	32	64
107	(CH2)9–CH CH2	CH3	50	51
108		CH3	59
109		CH3	46
110			48	65
111			nr	66
112			nr	66
113			51	67
114		CH3	51	68
115			47	69
116			33	70
117			23	71
118			21
119		CH3	50	72
120			40
121			50
122		C2H5	22	73
123			52	74
124			27	75
125		CH3	16	76
126			39
127			48	77
128		C2H5	62	78
129			62
130			38	79
131			nr	80
132
133
134
135		C2H5	14	81
136		C2H5	21
137			45	82
138	(CH2)3–Br	C18H37	70	83
139	(CH2)12–N3	C18H37	11

^anr – the yield is not provided.