Organoboronate synthesis

LUlo V, Geier MJ, Westcott SA, Fernandez E. Ni and Pd mediate asymmetric organoboron synthesis with ester fimctionahty at the P position. Org Biomol Chem. 2009 7 4674-4676. 

B. M. Mikhailov and Yu. N. Bubnov, Organoboron Compounds in Organic Synthesis, Harwood Academic PubHshers, London, 1984. 

Figure 25 Synthesis of naturally occuring phenylpropenoid (3-D-glucopyranosides. (a) allyl alcohol/immobilized (3-glucosidase with ENTP-4000, (b) Ac20/4-dimethylaminopyridine/pyridine, (c) organoboron reagents/Pd(OAcyCu(OAc)2/LiOAc/DMF, (d) K2C03/Me0H.

Much attention has recently been focused on organoboronic acids and their esters because of their practical usefulness for synthetic organic reactions including asymmetric synthesis, combinatorial synthesis, and polymer synthesis [1, 3, 7-9], molecular recognition such as host-guest compounds [10], and neutron capture therapy in treatment of malignant melanoma and brain tumor ]11]. New synthetic procedures reviewed in this article wiU serve to find further appHcations of organoboron compounds. 

In addition to hydroboration, haloboration and phenylboration have also been used in the synthesis of 7r-conjugated organoboron polymers (9)29 (Fig. 9) and polymers containing B—N bonds.30... 

The synthesis of luminescent organoboron quinolate polymers (21) (Fig. 15) via a three-step procedure starting from a silylated polystyrene has been communicated. The synthesis was initiated by the highly selective borylation of poly (4-trimethylsilylstyrene) (PS-Si), followed by the replacement of the bromine substituents in poly(4-dibromoborylstyrene) (PS-BBr) with substituted thienyl groups (R = H, 3-hexyl, 5-hexyl). In the final step, the 8-hydroxyquinolato moiety was introduced. The hexyl-substituted polymers efficiently emitted light at 513-514nm upon excitation at 395 nm.40... 

The synthesis of comblike organoboron polymer was examined (see scheme 2) by dehydrocoupling polymerization of hydroborane monomers bearing an... 

A synthesis of comblike organoboron polymer/boron stabilized imidoanion hybrids was examined via reactions of poly(organoboron halides) with 1-hexylamine and oligo(ethylene oxide) monomethyl ether and subsequent neutralization with lithium hydride (scheme 8). The obtained polymers (10) were amorphous soft solids soluble in common organic solvents such as methanol, THF, and chloroform. In the nB-NMR spectra (Fig. 11), neutralization of the iminoborane unit with lithium hydride... 

The regioselectivity of palladium-catalyzed additions of organoboronic acids to unsymmetrical alkynes is strongly dependent on steric and electronic effects (Scheme 12).62 Multi-component reaction has been reported for the synthesis of tetrasubstituted alkenes.58 The aryl group from an aryl iodide is generally added to the less hindered... 

N. Matsumi, M. Miyata, and Y. Chujo, Synthesis of organoboron Tr-conjugated polymers by hydroboration polymerization between heteroaromatic diynes and mesitylborane and their light emitting properties, Macromolecules, 32 4467-4469, 1999. 

Scheme 29 One-pot synthesis of a-C-glycosyl compounds from glycals using organo-aluminium and organoboron reagents.

---