Other Bisfunctional Tethers

To carry out tethered [3-i-2]-cycloadditions Nakamura et al. developed the new annulating reagents 123 [109, 110]. The reagents carry, in one molecule, two cyclopropenone acetals that are connected with an n-carbon methylene tether. Upon thermolysis in the presence of Cjq, the reagent undergoes [3-i-2]-cycloaddition reaction twice in a regio- and stereoselective manner to give Q- and C2-symmetrical bisadducts with cis-l - and cis-3-addition patterns, respectively. The selectivity varies 

Lull and co-workers showed that the tethered bisazides such as 2,2-dibenzyl-l,3-diazidopropane (124) undergo [3-t2] cycloadditions to adjacent [6 6]-bonds (cis-l addition). Thermal extrusion of N2 afforded a mixture of the corresponding cis-1-1,2,3,4-bisimino[60]fullerenes and twofold cluster-opened 2,3,4,5-bis-aza-homo[60]-fullerenes [36, 37, 111]. The reaction of with optically active bisazides yielded enantiomerically pure bis-azafullerenes with the same addition pattern [111]. 

Hirsch, F. Wudl, Angew. Chem. 1995, 107, 1462 Angew. Chem. Int. Ed. Engl. 

Lucchini, F. Wudl, Phys. Chem. Fullerenes Deriv., Proc. Int. Wintersch. Electron. Prop. Novel Mater. 1995,125. 

Birkett, R. Taylor N. K. Wachter M. Carano, E. Paolucci, S. Roeeia, 

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