Arylboronic acids and some of their derivatives have been found to undergo a rapid boron-lead exchange with lead tetra-acetate. In the presence of a catalytic amount of mercury(it) acetate, the reaction produces mainly the aryl-lead triacetate, and it has been developed as a convenient method for in situ generation of these useful electrophilic C-arylating reagents. The reaction allows the generation for the first time of meta-and para-phenylenebis( lead triacetate), compounds which behave as meta-and para-phenylene dication equivalents.

Tin( iv)-lead(iv) exchange and mercury( 11)-lead (iv) exchange reactions have been used to obtain 2-thienyl-lead triacetate (3), 2-thienyl -lead tribenzoate (4), 3-thienyl -lead triacetate (1 6), 2-furyl-lead triacetate (21 ), and 3-furyl-lead triacetate (31). In reactions with the P-dicarbonyl compounds (7), (I I), and (1 3), the above heteroaryl-lead compounds behaved as 2-thieny1, 3-thieny1, 2-furyl, and 3-fury1 cation equivalents respectively, giving the a-heteroaryl P-dicarbonyl compounds (8), (I 2), (1 4), (1 7), ( 18), ( 19), ( 25), ( 27), ( 28), (33), (34), and (35) in synthetically useful yields.

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