Premium
Heterodicarba‐ nido ‐hexaboranes from Hydroborations of Exocyclic Unsaturated Heterodiborolanes
Author(s) -
Greiwe Peter,
Pritzkow Hans,
Siebert Walter
Publication year - 2001
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/1099-0682(200106)2001:6<1599::aid-ejic1599>3.0.co;2-q
Subject(s) - chemistry , hydroboration , steric effects , nuclear magnetic resonance spectroscopy , medicinal chemistry , stereochemistry , derivative (finance) , cluster (spacecraft) , crystallography , organic chemistry , catalysis , computer science , financial economics , economics , programming language
The hydroboration of 1‐aza‐2,5‐diduryl‐3,4‐diisopropylidene‐ and 2,5‐diduryl‐1‐thia‐3,4‐diisopropylidene‐2,5‐diborolanes ( 1b , 2b ) with equimolar amounts of BH 3 ·thf leads to the corresponding 2‐aza‐4,5‐dicarba‐ and 4,5‐dicarba‐2‐thia‐ nido ‐hexaboranes 3c and 4e . When an excess of BH 3 ·thf reacts with the azadiborolane 1b the azadiborole derivative 5 is obtained as the main product. This surprising result is explained by the addition of three BH 3 ·thf moieties and the subsequent loss of B 3 H 7 ·thf. The reaction of the sterically less hindered tert ‐butylazadiborolane 1c with BH 3 ·thf yields two 2‐aza‐4,5‐dicarba‐ nido ‐hexaboranes ( 3d,e ), both of which carry a t Bu group in the apical position. A possible reaction pathway is suggested. The new heterocarboranes 3c,d,e and 4e are identified by multinuclear NMR spectroscopy and mass spectrometry. X‐ray crystallographic studies of 3c and 4e confirm the nido ‐arrangement of the cluster atoms.