Ethyl 3-Acetoxy-3-methyl-5-phenylpentanoate

Molecules 1998, 3, M60

Ethyl 3-Acetoxy-3-methyl-5-phenylpentanoate

Martin J. Stoermer^* and John T. Pinhey

Division of Organic Chemistry, School of Chemistry F11, The University of Sydney, N.S.W 2006, Australia.
^* Current address: Victorian College of Pharmacy, Monash University (Parkville Campus), 381 Royal Parade, Parkville, Victoria 3052, Australia. Phone: +61 3 990 39000, Fax: +61 3 99039582, e-mail: [email protected], http://synapse.vcp.monash.edu.au/martin/

Received: 27 February 1998 / Published: 6 March 1998

The general part of the experimental section [1] has been presented elsewhere. Ethyl 3-hydroxy-3-methyl-5-phenylpentanoate (1.00 g, 4 mmol) was refluxed in acetic anhydride (15 ml) for 3 hours. Water (20 ml) was added and the mixture was refluxed for 10 minutes, cooled and extracted with ether (50 ml). The ether extract was washed with water (4x100 ml), brine (30 ml), dried (Na₂SO₄), filtered and evaporated under reduced pressure. The residue was purified by radial chromatography (ethyl acetate/light petroleum 5:95) to yield ethyl 3-acetoxy-3-methyl-5-phenylpentanoate (0.876 g, 74%) as a colourless oil.

B.p. 160°/1.5 mmHg (Kugelrohr)

UV (ethanol) 269 (173), 260 (250), 254sh (212), 249sh (157) nm.

IR (CDCl₃) 1736(s, C=O), 1369, 1247(s), 1031, 761 cm^-1.

¹H-NMR (90 MHz, CDCl₃) 1.22 (3H, t, J 7.1 Hz, CO₂CH₂CH₃), 1.57 (3H, s, CH₃), 1.95 (3H, s, CH₃), 1.98-2.38 (2H, m, CH₂), 2.38-2.83 (2H, s, CH₂), 2.92 (2H, ABq, J_gem 14.4 Hz, CH₂), 4.07 (2H, q, J 7.1 Hz, CO₂CH₂CH₃), 6.93-7.30 (5H, m, ArH).

¹³C-NMR (15 MHz, CDCl₃) 14.02, 21.88, 23.96 (CH₃), 29.80, 40.51, 42.41, 60.13, (CH₂), 81.16 (quat, C3), 125.6, 128.2, 128.2 (CH), 141.4 (quat, C1'), 169.7 (quat, C=O), 170.0 (quat, C=O).

EI-MS 218(M⁺-AcOH, 29%), 173(16), 145(20), 144(56), 131(58), 130(22), 129(47), 105(10), 91(100).

Acknowledgment: The authors gratefully acknowledge financial support from the Australian Research Council and The University of Sydney.

References and Notes

1. Moloney, M.G.; Pinhey, J.T.; Stoermer, M.J. "Vinyl Cation Formation by Decomposition of Vinyl-lead Triacetates. The reactions of Vinylmercury and Vinyltin Compounds with Lead Tetraacetate." J. Chem. Soc. Perkin Trans. 1 1990, 10, 2645.

Sample Availability: No sample available.