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.
Supplementary materials
Supplementary File 1Supplementary File 2References and Notes
- Smith, D. tert-Butyl-3-methoxy-5,5-dimethyl-6-heptenoate. Molecules 1997, 2, M30. [Google Scholar] [CrossRef]
- Sample Availability: No sample available.
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