Allylboranes and the synthesis of diamond molecules

Abstract

The review summarizes our data on the synthesis of selected allylic, bicyclic, and highly strained cage boranes, investigations of their physicochemical properties, and applications of these com pounds. Procedures for the construction of boron polyhedral systems, transformations of 1 boraad amantane compounds into 1 hydroxyadamantanes and 1 azaadamantanes, and the synthesis of chiral derivatives of 1 boraadamantane and 3 borabicyclo[3.3.1]nonane are considered.

Borane‐Induced Dimerization of Arylallenes

“…characteristics of the X-ray crystal structures of 7band 7c are analogous to those of 7a,whereas the structure of 7ddeviates slightly.I nc ontrast to the gauche-type framework of the former it shows an antiperiplanar arrangement of the C3 À C2 and C4ÀC5 vectors [9] at the newly formed C3(sp 3 )ÀC4(sp 3 ) carbon-carbon single bond. We assumed that this reaction sequence probably starts with aH B(C 6 F 5 ) 2 hydroboration step [10] of the allene substrate, [11] followed by allylboration [12,13] of as econd arylallene equivalent. To investigate this assumption, we carried out an umber of experiments.…”

Borane-induced ring closure reaction of oligomethylene-linked bis-allenes

“…Internal allene allylboration 12 represents the important step of the ring-closure reaction sequence starting from 3 to form the products 5 . The compounds 5 themselves each contain an allylborane functionality which might show the respective reactivity towards added allene reagents.…”

Allylic boranes are chemist’s best friends: Reactivity, applications, new opportunities

“…The compound 21 was also transformed to 1,3,5-trimethylenecyclohexane (m.p. 34-35°C), which does not isomerizes to mesitylene on keeping in a closed bottle for 10 years [7]. This transformation was performed to demonstrate possibilities of boron chemistry.…”

“…This transformation was performed to demonstrate possibilities of boron chemistry. Application of 1-boraadamantanes in synthesis was reviewed [7,18].…”

“…For decades, b,c-unsaturated (allylic) boron compounds have been employed in organic synthesis due to their high reactivity, great variety reactions, high yields of the products and an excellent enantioselectivity of the allylboration of aldehydes and aldimines with chiral allylboranes [1][2][3][4][5] as well as the unique dynamic behaviour (borotropy [1,3], boron shifts) [6,7]. Various relatively simple and complicated natural compounds are available now through the use of allylic boranes.…”