Synthesis of endohedral metallofullerene glycoconjugates by carbene addition.

Endohedral metallofullerene glycoconjugates were synthesized under mild conditions by carbene addition using appropriate glycosylidene-derived diazirine with La(2)@I(h)-C(80). NMR spectroscopic studies revealed that the glycoconjugate consists of two diastereomers of [6,6]-open mono-adducts. The electronic properties were characterized using Vis/NIR absorption spectroscopy and electrochemical measurements.

Formation of N-heterocyclic, donor-stabilized borenium ions.

Cationic and zwitterionic boryl bromide species and a borenium-boryl bromide cation have been synthesised which represent new N-donor stabilised cationic boron compounds with β-diketiminate ligands. The unexpected borenium-boryl bromide results from a head-to-tail dimerisation of the corresponding zwitterionic boryl bromide accompanied by proton migration. The electronic nature of these new species was studied by DFT calculations.

Two regioisomers of endohedral pyrrolidinodimetallofullerenes M2@I(h)-C80(CH2)2NTrt (M = La, Ce; Trt = trityl): control of metal atom positions by addition positions.

The two regioisomers of endohedral pyrrolidinodimetallofullerenes M(2)@I(h)-C(80)(CH(2))(2)NTrt (M = La, Ce; Trt = trityl) were synthesized, isolated, and characterized. X-ray crystallographic analyses of [6,6]-La(2)@I(h)-C(80)(CH(2))(2)NTrt and [6,6]-Ce(2)@I(h)-C(80)(CH(2))(2)NTrt revealed that the encapsulated metal atoms are located at the slantwise positions on the mirror plane that parallels the pyrrolidine ring. Paramagnetic NMR analyses of [6,6]- and [5,6]-Ce(2)@I(h)-C(80)(CH(2))(2)NTrt were also carried out to clarify the metal positions.