Atropo-diastereoselective coupling of aryllithiums and arynes — variations around the chiral auxiliary
作者:David Augros、Boubacar Yalcouye、Anaïs Berthelot-Bréhier、Matthieu Chessé、Sabine Choppin、Armen Panossian、Frédéric R. Leroux
DOI:10.1016/j.tet.2016.01.047
日期:2016.8
The atropo-selective coupling of in situ generated arynes and aryllithiums bearing various chiralauxiliaries ortho to lithium (tert-butylsulfoxide, para-tolylsulfoxide, tartrate-derived chiral diethers and oxazolines) is described. Chiral oxazolines showed the best results in terms of yields of coupling products. Different reaction parameters like the nature of the aryne precursor, the oxazoline,
Regioselectivity in the Aryne Cross-Coupling of Aryllithiums with Functionalized 1,2-Dibromobenzenes
作者:Vincent Diemer、Manon Begaud、Frédéric R. Leroux、Françoise Colobert
DOI:10.1002/ejoc.201001283
日期:2011.1
Tri- and tetrasubstituted ortho-bromobiaryls have been synthesized in good-to-excellent yields by arynecross-coupling reactions starting from 1,3-dimethoxybenzene and functionalized1,2-dibromobenzenes. This study outlines the influence of the 1,2-dibromobenzene precursor as well as the reaction temperature on the outcome of the aryl-aryl bond formation and indicates, in the case of dissymmetrical
Stereoselective Synthesis of P-Chirogenic Dibenzophosphole–Boranes via Aryne Intermediates
作者:Vincent Diemer、Anaïs Berthelot、Jérôme Bayardon、Sylvain Jugé、Frédéric R. Leroux、Françoise Colobert
DOI:10.1021/jo3009098
日期:2012.7.20
A new aryne-mediated tandem cross-coupling/P-cyclization sequence starting from tertiary phosphine-boranes and 1,2-dibromobenzenes is reported. P-chirogenic dibenzophospholes become accessible in a regio-, chemo-, and diastereoselectiye way.
Efficient and Complementary Methods Offering Access to Synthetically Valuable 1,2-Dibromobenzenes
作者:Vincent Diemer、Frédéric R. Leroux、Françoise Colobert
DOI:10.1002/ejoc.201001217
日期:2011.1
in particular, reactions based on the intermediate formation of benzynes. This report describes short sequences for the synthesis of various derivatives based on regioselective bromination, ortho-metalation, and halogen/metal permutations. 1,2-Dibromo-3-iodobenzene (2f), 1,2-dibromo-4-iodobenzene (4c), and 2,3-di-bromo-1,4-diiodobenzene (5e) act as intermediates in these syntheses.
Aryne-mediated fluorination: Synthesis of fluorinated biaryls via a sequential desilylation–halide elimination–fluoride addition process
作者:Vincent Diemer、Juan Sanz Garcia、Frédéric R. Leroux、Françoise Colobert
DOI:10.1016/j.jfluchem.2011.02.017
日期:2012.2
An unusual aryne-mediated fluorination of aromatic ring systems during the desilylation of ortho-bromo-biphenyl-trimethylsilanes with tetrabutylammonium fluoride (TBAF) is described. In situ formation of an aryne and addition of fluoride affords fluorinated biphenyls. The structures have been undoubtfully confirmed by synthesis of authentic samples via Suzuki–Miyaura cross-coupling and X-ray analysis