tert-Butyl-3-methoxy-5,5-dimethyl-7-hydroxy-heptanoate

Molecules 1997, 2, M31

tert-Butyl-3-methoxy-5,5-dimethyl-7-hydroxy-heptanoate

Douglas A. Smith

The DASGroup, Inc., 1732 Lyter Drive, 2nd Floor, Johnstown, Pennsylvania 15905-1206, USA, and Department of Chemistry, University of Toledo, Toledo, Ohio 43606-3390, USA. Tel. +1 814 255 7859, Fax +1 814 255 3517, Email [email protected]

Received: 29 September 1997 / Published: 31 October 1997

Scheme

Hydroboration of tert-butyl-3-methoxy-5,5-dimethyl-6-heptenoate [1] with either BH₃ÖTHF or BH₃ÖMe₂S provided the terminal alcohol title compound, in unoptimized, nonreproducable and disappointingly low 30% yield. The poor yield is presumably due to isolation problems. Typically, this compound was not isolated but was directly oxidized without purification.

To a solution of the olefin (2.5g, 10.3 mmol) in dry THF (20 ml) at 0 ƒC, borane-methyl sulfide complex (1.1 ml, 11 mmol) was added slowly. The solution was warmed to room temperature, stirred for 2 hours, and cooled to 0 ƒC. 3N NaOH (2 ml) was added, then 30% H₂O₂ (2 ml). The reaction mixture was refluxed for 2 hours. After drying over Na₂SO₄, flash chromatography (1 : 1 pet ether : ether) gave tert-butyl-3-methoxy-5,5-dimethyl-7-hydroxy-heptanoate, as a colorless oil in 30% unoptimized yield.

¹H NMR (CDCl₃): d: 3.68 (m, 3H), 3.31 (s, 3H), 2.54 (dd, J = 14.6, 4.8Hz, 1H), 2.23 (dd, J = 14.6, 8.0Hz, 1H), 1.64 (m, 2H), 1.43 (s, 10H), 1.4 - 1.0 (m, 2H), 0.93 (s, 3H), 0.92 (s, 3H).

IR (film): 3450, 2960, 1730, 1370, 1160, 920, 845, 735.

References and Notes

Smith, D. tert-Butyl-3-methoxy-5,5-dimethyl-6-heptenoate, Molecules 1997, 2, M30.

Sample Availability: No sample available.