Steroids CCXC. The hydroboration of a tetracyclic diene

✍ Scribed by J.P. Turnbull; J.H. Fried

• Publisher: Elsevier Science
• Year: 1966
• Tongue: French
• Weight: 235 KB
• Volume: 7
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)99687-x

✦ Synopsis

The stereochemistry of hydroboration of rigid systems can usually be predicted from steric parameters which direct the reagent to the less hindered side of the molecule (3a,b) We wish to report that hydroboration of the synthetic (f) tetracycle Ia(4,5) carried out with tert-2,3_dimethylbutylborane(6) followed by oxidation with hydrogen peroxide affords R cH30@O&* cH3 III a -R:THP b -R:H c -R:CH2@ stereospecifically the unsaturated 14-iso-15S-alcohol IIa (7,8,9) [m.p. 135-136"; hmax 273 rnk (log E 4.23).