Compound 35

2-((1s,3s)-1-(4-chlorophenyl)-3-phenylcyclobutyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

From: Carbopalladation of C–C σ-bonds enabled by strained boronate complexes

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Compound data: NMR

Compound data: Crystallographic data

Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

According to General Procedure A outlined for compound 6, 4-chlorophenyl pinacol boronic ester (57 mg, 0.24 mmol, 1.0 equiv) and phenyl triflate (0.05 mL, 0.29 mmol, 1.2 equiv) were coupled to give a crude residue (>98:2 d.r. by crude NMR) that was purified by flash column chromatography (SiO2; 95:5 pentane:Et2O) to afford the corresponding cyclobutane 35 (59 mg, 67 %, >98:2 d.r.) as a white solid. m.p.: 123 – 127 °C (Et2O). TLC: Rf = 0.21 (95:5 pentane:Et2O). 1H NMR (400 MHz, CDCl3) δ 7.28 – 7.14 (m, 7H, 7× ArH), 7.09 – 7.05 (m, 2H, 2× ArH), 3.59 – 3.50 (m, 1H, ArCCH), 3.02 – 2.98 (m, 2H, ArCH(CHaHb)2), 2.35 – 2.30 (m, 2H, ArCH(CHaHb)2), 1.23 (s, 12H, Bpin) ppm. . 13C NMR (101 MHz, CDCl3) δ 147.3 (ArC), 145.5 (ArC), 130.4 (ArC), 128.3 (ArCH), 128.3 (ArCH), 127.1 (ArCH), 126.5 (ArCH), 126.0 (ArCH), 83.9 (OC(CH3)2), 39.4 (ArCCH(CH2)2), 36.6 (ArCCH), 24.7 (OC(CH3)2) ppm. . HRMS (m/z): (ESI) calc’d for C22H26BClNaO2 [M+Na]+: 391.1611, found: 391.1609. IR (solid state) νmax: 2971, 1491, 1354, 1317, 1139, 1106, 1090, 841, 758, 699 and 523 cm−1. X-ray Crystal Structure: CCDC number: 1847416.