Abstract
A comparative study on the reactivity and selectivity of arylcopper species in reactions with boron halides was performed. Mesitylcopper reacts with BX3 (X=Cl, Br) in toluene at low temperature under highly selective formation of the monosubstituted boranes MesBX2. The dimesitylboranes Mes2BX are gradually formed with a twofold excess of the organocopper reagent at elevated temperature. In contrast, pentafluorophenylcopper shows a tendency for formation of B(C6F5) 3 in reactions with BX3 irrespective of the stoichiometry used, suggesting a strong impact of electronic factors on the selectivity of the aryl transfer reaction. New procedures for the synthesis of the pentafluorophenylboron halides C6 F5BX2 (X=Cl: 57%; X=Br: 62%) and of tris(pentafluorophenyl)borane (80%) and related mixed-substituted triarylboranes from the base-free isolable pentafluorophenylcopper precursor have been developed.
Original language | English (US) |
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Pages (from-to) | 134-142 |
Number of pages | 9 |
Journal | Journal of Organometallic Chemistry |
Volume | 681 |
Issue number | 1-2 |
DOIs | |
State | Published - Sep 12 2003 |
All Science Journal Classification (ASJC) codes
- Biochemistry
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
- Materials Chemistry
Keywords
- Arylation
- Boron
- Copper
- Lewis acid
- Organoborane
- Organocopper reagent