Synthesis of Unsaturated Organotrifluoroborates via Wittig and Horner−Wadsworth−Emmons Olefination
作者:Gary A. Molander、Ruth Figueroa
DOI:10.1021/jo060863w
日期:2006.8.1
stereoselective synthesis of unsaturated organotrifluoroborates by using the Wittig and Horner−Wadsworth−Emmons olefination is described. These reactions were general for both alkyl- and aryltrifluoroborates. The synthesis of di- and trisubstituted olefins was achieved by using formyl- and acetyl-substituted organotrifluoroborates. The products were isolated in moderate to excellent yield. The Wittig reaction
Suzuki−Miyaura Cross-Coupling Reactions of Benzyl Halides with Potassium Aryltrifluoroborates
作者:Gary A. Molander、Maxwell D. Elia
DOI:10.1021/jo061699f
日期:2006.11.1
[GRAPHICS]The palladium-catalyzed cross-coupling of potassium aryltrifluoroborates with benzylic halides occurs in good yield with high functional group tolerance. The increased stability of potassium aryltrifluoroborates compared to other boron coupling partners makes this an effective route to functionalized methylene-linked biaryl systems.
Functionalization of Organotrifluoroborates: Reductive Amination
作者:Gary A. Molander、David J. Cooper
DOI:10.1021/jo800383e
日期:2008.5.1
Herein we report the conversion of aldehyde-containing potassium and tetrabutylammonium organotrifluoroborates to the corresponding amines through reductive amination protocols. Potassium formate facilitated by catalytic palladium acetate, sodium triacetoxyborohydride, and pyridine borane have all served as effective hydride donors, reducing the initially formed imines or iminium ions to provide the corresponding amines.
Wittig reaction of formyl-substituted organotrifluoroborates and stabilized phosphonium ylides in an aqueous medium
作者:Gary A. Molander、Roberta A. Oliveira
DOI:10.1016/j.tetlet.2007.11.205
日期:2008.2
The synthesis of unsaturated organotrifluoroborates using the Wittig alkenation is described. These transformations to disubstituted alkenes were achieved by using formyl-substituted organotrifluoroborates and stabilized ylides using water as a solvent. The products were isolated in moderate to excellent yields and the reaction gave preferentially the E-isomer. (c) 2007 Published by Elsevier Ltd.
<sup>1</sup>
H, <sup>13</sup>
C, <sup>19</sup>
F and <sup>11</sup>
B NMR spectral reference data of some potassium organotrifluoroborates
作者:Roberta A. Oliveira、Ricardo O. Silva、Gary A. Molander、Paulo H. Menezes
DOI:10.1002/mrc.2467
日期:2009.10
Complete (1)H, (13)C, (19)F and (11)BNMRspectraldata for 28 potassiumorganotrifluoroborates are described. The resonance for the carbon bearing the boron atom is described for most of the studied compounds. A modified (11)BNMR pulse sequence was used and better resolution was observed allowing the observation of (11)B-(19)F coupling constants for some of the studied compounds.