BrCCBr.Cl[Si](C)(C)C.I[CH:11]1[CH2:14][N:13]([C:15]([O:17][C:18]([CH3:21])([CH3:20])[CH3:19])=[O:16])[CH2:12]1.O1C=CC=C1P(C1OC=CC=1)C1OC=CC=1.[C:38]([C:41]1[CH:48]=[C:47]([CH3:49])[C:44]([C:45]#[N:46])=[C:43](I)[C:42]=1[O:51][CH3:52])(=[O:40])[CH3:39]>CN(C)C(=O)C.[Zn].C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.[Pd].[Pd]>[C:38]([C:41]1[C:42]([O:51][CH3:52])=[C:43]([CH:11]2[CH2:14][N:13]([C:15]([O:17][C:18]([CH3:21])([CH3:20])[CH3:19])=[O:16])[CH2:12]2)[C:44]([C:45]#[N:46])=[C:47]([CH3:49])[CH:48]=1)(=[O:40])[CH3:39]Zinc (1.70 g, 26.0 mmol) and celite (oven dried, 500 mg) were ground together in a flask until the solids appeared homogenous, the flask was heated with a heat gun while under high-vac for 5 minutes and then back-filled with nitrogen. The solids were suspended in N,N-dimethylacetamide (4.2 mL) and 1,2-dibromoethane (0.13 mL, 1.5 mmol) was added. The reaction mixture was heated at 70° C. for 30 min and then cooled to room temperature. Chlorotrimethylsilane (0.16 mL, 1.3 mmol) was added dropwise and stirring was continued for 2 hrs at room temperature. A solution of tert-butyl 3-iodoazetidine-1-carboxylate (2.70 g, 9.52 mmol) in N,N-dimethylacetamide (4.35 mL) was then added slowly and the resulting mixture was heated at 50° C. for 2 hrs. The zinc-iodo reagent was allowed to cool to room temperature and was taken up in a syringe and filtered through a PTFE filter (adapted with a needle) directly into a suspension of tris(dibenzylideneacetone)dipalladium(0) (0.111 g, 0.121 mmol) and tri-(2-furyl)phosphine (0.056 g, 0.24 mmol) and 4-acetyl-2-iodo-3-methoxy-6-methylbenzonitrile (2.0 g, 6.3 mmol) in N,N-dimethylacetamide (19.6 mL) pre-degassed by bubbling N2. The reaction mixture was degassed with nitrogen again and heated to 70° C. After heating for 30 minutes the reaction was complete by LC/MS. This was allowed to cool, taken up in ethyl acetate and washed with water, brine, dried over magnesium sulfate and concentrated to give the crude product as an oil. The product was purified by FCC on silica gel eluting hexane; ethyl acetate gradient to give tert-butyl 3-(3-acetyl-6-cyano-2-methoxy-5-methylphenyl)azetidine-1-carboxylate as a clear oil. (1.8 g, 82%). LCMS calculated for C15H17N2O4 (M+H)+: m/z=289.1; found: 289.1.
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