CC(C)(C)C(=O)NC1CC1>C1=CCCC=CCC1.C1=CCCC=CCC1.C1CCCCC1.CC1(C)OBOC1(C)C.C[OH2+].C[OH2+].Cc1cnc2c(ccc3c(C)c(C)cnc32)c1C.[Ir].[Ir]>CC(C)(C)C(=O)NC1CC1B1OC(C)(C)C(C)(C)O1A mixture of 3,4,7,8-tetramethyl-1,10-phenanthroline (46.9 mg, 71 µmol) and [Ir(OMe)(cod)]2 (33.5 mg, 0.14 mmol) in cyclohexane (5 mL) was stirred at room temperature for 15 min in a Schlenk flask under N2 atmosphere. N-Cyclopropylpivalamide (1a: 2.0 g, 14 mmol), 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (HBpin: 3.08 mL, 21 mmol) and cyclohexane (20 mL) were added to the mixture under N2 flow. Then, the reaction mixture was heated at 80 °C for 18 h under N2 atmosphere. The reaction mixture was concentrated in vacuo. The resultant residue was purified by silica gel flash column chromatography (chloroform/acetone = 25:1 to 20:1). The collected fractions were purified again by silica gel column chromatography (hexane/ether = 1:2 to 1:4) to give 2.33 g of the product 2a as a white solid in a 62% yield. NOE was observed between H1 and H2 . This result indicates that boronate 2a has cis configuration.
Wird geladen…
