Wilkinson's catalyst in benzene at 20°C, 25 min; distn.;

1: BH3*THF View Scheme

molecular sieves in chloroform-d1 byproducts: H2O; addn. of catechol to CDCl3 soln. of boronic acid deriv., refluxing for 2h in presence of molecular sieves; filtration, not isolated, NMR;

(i) BH3*THF, (ii) /BRN= 2024703/; Multistep reaction;

1: 2-cyclopentyl-benzo[1,3,2]dioxaborole With ethanol in dichloromethane T=0 - 20°C; 0.25 h; Inert atmosphere; 2: N-phenyl-maleimide; 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical With N,N'-dimethyl-N,N'-propyleneurea in dichloromethane T=20°C; Inert atmosphere;