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Updated: May 15, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
(3aS,4S,6S,7aR)-Hexahydro-3a,5,5-trimethyl-2-phenyl-4,6-methano-1,3,2-benzodioxaborole
Tore Lejon1, Olga V Gozhina, Victor N Khrustalev
1Department of Chemistry, Faculty of Science and Technology, University of Tromsø, N-9037 Tromsø, Norway.
Abstract:
The mol-ecule of the title compound, C(16)H(21)BO(2), comprises a chiral fused tricyclic system containing five-membered (1,3,2-dioxaborolane), six-membered (cyclo-hexa-ne) and four-membered (cyclo-butane) rings. The 1,3,2-dioxaborolane ring is almost planar (r.m.s. deviation = 0.035 Å), and the syn H and Me substituents at this ring are in an eclipsed conformation. The cyclo-hexane and cyclo-butane rings adopt sofa and butterfly conformations, respectively. The B atom has a trigonal-planar configuration (sum of the bond angles = 360.0°). The phenyl ring is practically coplanar with the 1,3,2-dioxaborolane ring [dihedral angle between the ring planes = 1.96 (8)°]. The absolute structure was determined from the known configuration of (+)-pinanediol which was used in the synthesis. In the crystal, weak C-H⋯π(Ph) inter-actions occur.
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