Various olefins, especially those bearing electron donating groups, were successfully arylated by arenediazonium salts in the presence of a catalytic amount of palladium(O) complexes. An arylpalladium species was supposed to be an intermediate in this reaction.

H and 13C NMR relaxation times ( T , ) of ethoxycarbonylmethyl derivatives of p-t-butylcalix[n]arenes have been determined at 90 MHz and 36 "C in [2H,]THF. It was found that these calixarenes feature a 'seesaw motion' around the ArCH2Ar linkage as a central support and that this molecular motion is largely suppressed through complexation with Na'.

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Rhodium complexes (RhClL3, RhCl(CO)L2, [RhCl(COD)]2; L=PPh3) catalyze hydrostannation of terminal acetylenes (RC≡CH; R=Ph, Me3Si, R1OC(R2)(R3), and R1OCH2CH2; R1=THP, OAc; R1, R2=H, Me) with Bu3SnH to produce R(Bu3Sn)C=CH2 selectively. Other transition metal complexes [MCl2L2(M=Ni, Pd, Pt, Co)] are also active for the hydrostannation, but with less selectivity.

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