Br[C:2]1[CH:7]=[CH:6][C:5]([CH3:8])=[CH:4][CH:3]=1.[Mg].II.[N:12]1[CH:17]=[CH:16][CH:15]=[C:14]([CH3:18])[C:13]=1[CH3:19].Cl[C:21]([O:23][C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1)=[O:22]>O1CCCC1>[CH3:19][C:13]1[N:12]([C:21]([O:23][C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)=[O:22])[CH:17]([C:2]2[CH:7]=[CH:6][C:5]([CH3:8])=[CH:4][CH:3]=2)[CH:16]=[CH:15][C:14]=1[CH3:18]A solution of p-bromotoluene (13.5 g) in 50 ml of tetrahydrofuran was added to magnesium (1.5 g) and 1 crystal of iodine in a little tetrahydrofuran, and the mixture was refluxed for 1 hour. In a separate flask, a solution of 2,3-lutidine (6.5 g) in 100 ml of tetrahydrofuran was cooled to about -60° C., and the magnesium complex prepared above added, followed by phenyl chloroformate (8 ml). The mixture was stirred for 1 hour at -60° C., then at room temperature overnight. The solvent was removed under reduced pressure, the residue partitioned between ether and 200 ml of 20% ammonium chloride, the organic layer washed with water, followed by dilute hydrochloric acid. The solvent was evaporated under reduced pressure, and the residue flash-chromatographed on silica gel, eluting with 1% ethyl acetate in heptane, to yield 12.4 g of 1,6-dihydro-2,3-dimethyl-6-(4-methylphenyl)-1-phenoxycarbonyl pyridine, m.p. 106° C.
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