Br[C:2]1[N:7]=[C:6]([NH:8][C:9](=[O:14])[C:10]([CH3:13])([CH3:12])[CH3:11])[CH:5]=[CH:4][CH:3]=1.Cl[P:16]([C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1)[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1.O>C(OCC)C>[C:23]1([P:16]([C:17]2[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=2)[C:2]2[N:7]=[C:6]([NH:8][C:9](=[O:14])[C:10]([CH3:13])([CH3:12])[CH3:11])[CH:5]=[CH:4][CH:3]=2)[CH:24]=[CH:25][CH:26]=[CH:27][CH:28]=11.00 g (3.89 mmol) of 6-bromo-2-pivaloylaminopyridine from example 14.2.1 was dissolved in 10 ml of diethyl ether and admixed at 0° C. with 3.64 ml (8.00 mmol) of (iso-C3H7)MgBr (2.2M in Et2O). The suspension was stirred at 0° C. for 18 h and then admixed with 0.7 ml (0.86 g, 3.89 mmol) of chlorodiphenylphosphine. The mixture was allowed to warm to ambient temperature overnight and was then hydrolyzed by adding 10 ml of dist. H2O. The resulting phases were separated and the aqueous phase was extracted twice with 50 ml each time of ethyl acetate. The organic phases were combined and dried over Na2SO4, and the solvent was removed under reduced pressure. The residue was filtered together with dichloromethane through a short silica gel column (2×10 cm) and the solvent was removed under reduced pressure. The resulting oil was crystallized by digesting with petroleum ether/diethyl ether (40/60). The crystals were filtered off and washed with petroleum ether/diethyl ether (40/60). 0.38 g (1.05 mmol, 27.0%) of 6-(diphenylphosphino)-2-pivaloylaminopyridine was obtained as a solid.
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