Pyridine → HCID 67793288, compound

Participants

Reaction Steps

A solution of ethyl chloroformate (1.74 g, 0.016 mol) in dichloromethane (10 mL) was added dropwise over a 1 hour period to a cold (5° C.) solution of 4-oxo-β-ionol (3.33 g, 0.016 mol, which may be prepared as described by R. Kaiser and D. Lamparsky, Helv. Chim. Acta, 1978, 61, 2328-2335), pyridine (1.28 g, 0.016 mol) and dichloromethane (30 mL). After stirring the mixure at 5°-10° C. for 2 hours it was added to ice water (20 mL) The organic layer was washed with 5% phosphoric acid solution until neutral and dried over sodium sulfate. The solvent was removed and the residue chromatographed. Kugelrohr distillation (bath temp. 150° C., 0.5 mm) gave 2.0 g (GLC purity; 85%) of 3-(3-hydroxy-1-butenyl)-2,4,4-trimethyl-2-cyclohexen--one ethyl carbonate. 1H-NMR (CDCl3) δ1.12 (6H,s), 1.35 (3H,d,J=7Hz), 1.40 (3H,t,J=7Hz), 1.77 (3H,s), 1.7-2.7 (4H,m), 4.20 (2H,q,J=7Hz), 4.8-5.4 (1H,m), 5.53 (1H,dd,J=16 and 6Hz), 6.31 (1H,d,J=16Hz); IR (film)vmax 2960, 1745, 1665, 1460, 1440, 1365, 1250 cm-1 ; MS m/e 280, 265, 236, 207, 191, 134.

Provenance & Evidence