ISSN:
1572-9001
Schlagwort(e):
Diboracyclopropenyl anion
;
diboriranyl anion
;
aromatic stabilization
;
ab initio
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Abstract The most stable structure of CB2H3 −, as established computationally, is the aromatic diboracyclopropenyl (diboriranyl) anion (5), while open-chainC 2v, isomer H2BCBH (7) is only 3 kcal/mol higher in energy at the QCISD(T)/6-311 +G**//MP2/6-31+G*+ZPE (HF/6-31 +G*). The 47-kcal/mol barrier between cyclic,5, and open-chain,7, structures suggests that both of them may be observed. The aromatic stabilization energy of the diboriranyl anion (18 kcal/mol) is half the value in the isoelectronic cyclopropenium ion, C3H3 +. The computed, by IGLO method (5a), and experimental (6a) chemical shifts,δ(13C) andδ(11B), agree within 4 ppm range. The theoretical vibrational frequencies of the most stable isomers,5 and7, are presented for experimental verification of these species.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF02293115
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