[60]fullerenoacetyl chloride as a versatile precursor for fullerene derivatives: efficient ester formation with various alcohols.

[reaction: see text] [60]Fullerenoacetyl chloride, one of the reactive derivatives of [60]fullerenoacetic acid, was isolated and identified for the first time. This acid chloride was easily synthesized in good yield from tert-butyl [60]fullerenoacetate through two steps. In the presence of 4-(dimethylamino)pyridine as a base, the acid chloride smoothly reacted with various alcohols under mild conditions to give the corresponding esters including [60]fullerene-biomolecule hybrids in moderate to high yields.

Unexpected switch in regioselectivity of tether-directed Bingel-type biscyclopropanations depending on the leaving groups at tethered active ethylene moieties.

The regioselectivity of tether-directed Bingel-type biscyclopropanations of [60]fullerene was switched depending on the leaving groups at tethered active methylene moieties; the reactions of [60]fullerene with unhalogenated tethered bis(active methylene) derivatives/I2 and with brominated derivatives in the presence of 1,7-diazabicyclo[5.4.0]undec-7-ene gave trans-4-adducts predominantly, while the reactions with chlorinated derivatives afforded equatorial-adducts almost exclusively.