Hydroboration of the diene forming the pheromones are found to yield the required Z-11-hexadecenol alcohol, but the hydroboration should be regioselective towards the terminal double bond.
Hydroboration of 1,11-hexadecadiene and Synthesis of Z-11-hexadecen-1-ol
Several procedures adopted for the regioselective hydroboration of the terminal double bond.
Rovia I Virgili, Spain), presents 15 papers demonstrating some of these applications, covering transformations such as hydrogenation, hydroamination, hydroboration
, C--C bond formation, carbonylation, and cyloadditions, as well as recent catalytic system using iridium nanoparticles and the use of relevant ligands as carbenes and pincer ligands.
Ming Chen, The Scripps Research Institute, Scripps Florida -- Development of Functionalized Chiral Allylboranes via Allene Hydroboration
and Applications in Natural Product Synthesis
His research involves catalyst system development and mechanistic elucidation for rhodium-catalyzed hydroboration
In the light of the information referred to above we made an attempt to obtain diketones 2 and 3 directly from lactone 1 by hydroboration (Scheme 2).
The applied hydroboration procedure leads to a chromatographically inseparable mixture of hydroxylated diasereo- and regioisomers 4a and 4b, in a ratio of 3 : 1 (determined by NMR).
Primary amine functionalization was completed in refluxing THF by performing hydroboration
with 9-BBN followed by amination with hydroxylamine-o-sulfonic acid.
The pendant olefin is then converted into an alkyl borane by hydroboration
and the ring is formed using Suzuki-Miyaura technology (Scheme 1).
These organosilica hybrid materials with crystalline mesoporosity, tailored through organic chemistry to be mono-, hi- or tri-functional, offer unique potential for scientific and technological advances in numerous application areas because the organic function and the inorganic framework can be tailo red through chemistry to tune their mechanical, electrical, optical, magnetic, catalytic, separation and chemical reactivity properties (see the group's recent paper 'Novel Bifunctional Periodic Mesoporous Silicas, BPMOs -- Synthesis, Characterization, Properties and in situ Selective Hydroboration
-- Alcoholysis of Functional Groups', Journal of the American Chemical Society, 123, 8520-8530, 2001).
Marder has developed several iridium and rhodium-based catalysts for the hydroboration
of organic substrates.