1,3-bis(2,6-di-(i-propyl)phenyl)-4,5-dihydroimidazolium tetrafluoroborate; lithium hexamethyldisilazane; bis(dibenzylideneacetone)-palladium(0) in toluene T=20°C; 12 h;

1: propionic acid tert-butyl ester With sodium hexamethyldisilazane in toluene T=20°C; 0.166667 h; Inert atmosphere; 2: chlorobenzene With [P(t-Bu)3Pd(μ-Br)]2 in toluene T=20°C; 4 h; Inert atmosphere;

(1,2,3,4,5-pentaphenylferrocen-1'-yl)-di-tert-butylphosphine; bis(dibenzylideneacetone)-palladium(0) in tetrahydrofuran T=20°C; 4 h; Inert atmosphereSealed tube; Reagent/catalystConcentrationTemperature;

boron trifluoride diethyl etherate in dichloromethane; cyclohexane 16 h; Ambient temperature;

1: 76 percent Chromat. / lithium amide / liquid ammonia; hexane / 1.33 h / Heating; Irradiation 2: diisopropyl amide View Scheme

1: 76 percent Chromat. / lithium amide / liquid ammonia; hexane / 1.33 h / Heating; Irradiation 2: diisopropyl amide View Scheme

1: With 2,2,2-trimethylacetic acid; (S)-(+)-1-tert-butyldiphenylsilyloxy-3-(3'-methyl-3'H-imidazol-4'-yl)-2-(2'',4'',6''-triisopropylbenzenesulfonylamino)propane in tetrachloromethane T=-20°C; 24 h; Inert atmosphere; 2: With hydrogenchloride; water in tetrachloromethane Inert atmosphere;

1: 2-phenyl-propanoic pivalonic anhydride; tert-butyl alcohol With 2,2,2-trimethylacetic acid; (S)-(+)-1-tert-butyldiphenylsilyloxy-3-(3'-methyl-3'H-imidazol-4'-yl)-2-(2'',4'',6''-triisopropylbenzenesulfonylamino)propane in tetrachloromethane T=-20°C; 24 h; Inert atmosphere; 2: benzylamine in tetrachloromethane Inert atmosphere;

lithium diisopropyl amide 1.) THF, -78 deg C, 30 min, 2.) -78 deg C -> r.t., 1 h; Yield given. Multistep reaction;

n-butyllithium; diisopropylamine; trifluoroacetic acid in tetrahydrofuran; hexane byproducts: C6H5O(C6H6)CHCH3COOC(CH3)3; addn. of soln. of BuLi in hexane at -5°C to a soln. of the amine in THF, stirring for 15 min, cooling to -78°C,addn. of the ester and the Cr-compd. and the acid, warm to room temp. with stirring,; extn. after 10 h, chromy., recrystn. from acetone;