[CH3:1][C:2]1([CH3:16])[CH2:6][C:5](B2OC(C)(C)C(C)(C)O2)=[CH:4][CH2:3]1.Br[C:18]1[O:22][N:21]=[C:20]([C:23]([O:25][CH2:26][CH3:27])=[O:24])[C:19]=1[CH3:28].C([O-])([O-])=O.[K+].[K+].C(Cl)Cl>C(#N)C.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].O>[CH3:16][C:2]1([CH3:1])[CH2:6][C:5]([C:18]2[O:22][N:21]=[C:20]([C:23]([O:25][CH2:26][CH3:27])=[O:24])[C:19]=2[CH3:28])=[CH:4][CH2:3]1To a 2-5 mL microwave vial containing a solution of 2-(4,4-dimethylcyclopent-1-en-1-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (214 mg, 0.966 mmol) in acetonitrile (2 mL), ethyl 5-bromo-4-methylisoxazole-3-carboxylate (Intermediate A) (226 mg, 0.966 mmol) was added followed by K2CO3 (400 mg, 2.90 mmol), PdCl2(dppf).CH2Cl2 adduct (Alfa Aesar) (79 mg, 0.097 mmol) and water (1 mL). The vial was flushed with nitrogen, sealed and heated in the microwave (Biotage Smith Initiator) at 90° C. for 1 hour. The resulting mixture was filtered through Celite®, washing with EtOAc (50 mL). The filtrate was washed with water (50 mL), brine (50 mL), dried over MgSO4, filtered and concentrated under reduced pressure to give a brown oil. The crude material was adsorbed onto silica and purification by chromatography eluting with 100% iso-hexane afforded the title compound;
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