hexamethyl-benzene; potassium carbonate in water; toluene (under N2, Schlenk); toluene and aq. K2CO3 added to tube with Pd-complex, C6H5B(OH)2 and hexamethylbenzene, stirred at 50°C for 10 min; monitored by MS;

P4; NaB(C6H5)4; H2O in tetrahydrofuran byproducts: NaBr, H3PO3, H3PO4; (N2); NaB(C6H5)4 added to a soln. of Pd complex, stirred at 50°C for 1 h, a soln. of P4 added dropwise, stirred at 50°C for 1 h, deaerated H2O added; not isolated, detected by MS;

P4; NaB(C6H5)4; H2O in tetrahydrofuran byproducts: NaBr, H3PO3, H3PO4; (N2); NaB(C6H5)4 added to a soln. of Pd complex, stirred at 50°C for 1 h, a soln. of P4 added dropwise, stirred at 50°C for 1 h, deaerated H2O added; not isolated, detected by MS;