Cyclopentadiene → HCID 12137773, compound

Participants

Reaction Steps

Prepared according to the general procedure with (E)-hex-2-enal (142 μL, 1.22 mmol), cyclopentadiene (302 μL, 3.66 mmol), and 5 (16 mg, 0.061 mmol) to provide the title compound as a colorless oil in 92% yield (184 mg, 1.12 mmol) after silica gel chromatography (10% EtOAc/hex); 1.0:1.0 endo:exo; endo 90% ee; exo 86% ee. Product ratios were determined by GLC (Bodman Γ-TA column, 100° C. isotherm, 23 psi); exo isomers tr=25.6 min and 26.7 min, endo isomers tr=30.2 min and 30.9 min. 1H NMR, 13C NAMR and IR data for the endo isomer were consistent with previously reported values (Ishiara et al. (1998), supra). Exo isomer: IR (CH2Cl2)1719, 1466, 1456 cm−1; 1H NMR (400 MHZ, CDCl3)δ9.76 (d, J=2.7 Hz, 1 H, CHO), 6.19 (dd, J=5.6, 3.2 Hz, 1H, CH=CH), 6.11 (dd, J=5.6, 2.9 Hz, 1H, CH=CH), 3.00 (br s, 1H, CHCH=CH), 2.85 (br s, 1H, CHCH=CH), 2.23-2.30 (m, 1H, CHCH2CH2), 1.72-1.76 (m, 1H, CHCHO), 1.00-1.47 (m, 6H, CHCH2CH, CH2CH2CH3), 0.86 (t, J=7.2 Hz, 3H, CH2CH3); 13C NMR (100 MHZ, CDCl3)δ203.9, 136.0, 135.9, 58.7, 47.0, 45.7, 44.8, 41.6, 36.4, 21.6, 14. 1; HRMS (EI) exact mass calcd for (C11H16O) requires m/z 164.1201, found m/z 164.1200; [α]D=+89.4 ©=2.7, CHCl3).

Provenance & Evidence