1: With tert.-butyl lithium in tetrahydrofuran; pentane T=-78°C; 1 h; 2: With boric acid trimethyl ester in tetrahydrofuran; pentane T=-78 - 20°C; 3 h; 3: With hydrogenchloride in tetrahydrofuran; water; pentane

1: With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 0.5 h; 2: With tributoxyborane in tetrahydrofuran; hexane T=-78°C; 1 h;

n-butyllithium in tetrahydrofuran; hexane T=20°C; 2 h; Inert atmosphere;

1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione in dimethyl sulfoxide T=20°C; 5 h; Inert atmosphere;

1.1: toluene-4-sulfonic acid / toluene / 20 h / |Reflux; |Dean-Stark 2.1: n-butyllithium / hexane; tetrahydrofuran / 0.5 h / -78 °C 2.2: 1 h / -78 °C View Scheme

Mg; aq. H2SO4; KOH in tetrahydrofuran; diethyl ether byproducts: BuOH, Mg(OH)2, MgBr2; dropwise addn. of the grignard compd. of the acetal in THF to mixt. of B(OC4H9)3 in THF (under N2, -68°C, under stirring), stirred after thawing (1 h), evapn. of volatiles (20°C, 1 Torr), addn. of 1 M H2SO4 to soln. of the residue in ether; extn. with ether, evapn. of ether (vac.), addn. of KOH to aq. phase, after addn. of water azeotropic distn. of H2O/ BuOH in vac., residue acidified with 1 M H2SO4, refluxed (30 min), filtered, cooling of the filtrate, recrystn. from hot H2O; elem. anal.;

1,3,5,7-tetra-azatricyclo[5.1.1.13,5]decane

tetrahydroxydiboron; chloro(2-dicyclohexylphosphino-2',4',6'-triisoporpyl-1,1'-biphenyl)[2-(2'-amino-1,1'-biphenyl)] palladium (II); potassium acetate; 2-(dicyclohexylphosphino)-2',4',6'-tri-i-propyl-1,1’-biphenyl in ethanol T=80°C; 20 h; Inert atmosphere;

tetrahydroxydiboron; chloro(2-dicyclohexylphosphino-2',4',6'-triisoporpyl-1,1'-biphenyl)[2-(2'-amino-1,1'-biphenyl)] palladium (II); potassium acetate; 2-(dicyclohexylphosphino)-2',4',6'-tri-i-propyl-1,1’-biphenyl in methanol T=80°C; 4 h; Inert atmosphere;

1: nBuLi; B(O-iPr)3 / tetrahydrofuran; hexane / 20 °C 2: HCl; water / 7 h / 20 °C View Scheme