کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5275013 | 1385523 | 2011 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: The development of an approach toward sterically-hindered chiral 2â²-aryl-1,1â²-binaphthalenes functionalized at position 2 The development of an approach toward sterically-hindered chiral 2â²-aryl-1,1â²-binaphthalenes functionalized at position 2](/preview/png/5275013.png)
Several approaches were examined for the preparation of 1,1â²-binaphthalene derivatives bearing sterically demanding ortho-substituted aryl at position 2â² which are suitable for further functionalization at position 2. Steric hindrance of ortho-substituted aryl groups was critical for the approach through BINOL monotriflate. Among variations of cross-coupling reactions of 2,2â²-dihalo-1,1â²-binaphthalenes, Negishi arylation of an enantiopure 2,2â²-dibromide was found to be the method of choice for regioselective and stereoconservative preparation of the target 2â²-monoarylated precursor. Functionalization of the latter at position 2 was demonstrated by bromine substitution via lithiation followed by the reaction with several electrophiles.
Among variations of cross-coupling reactions of 2,2â²-dihalo-1,1â²-binaphthalenes, Negishi arylation of an enantiopure 2,2â²-dibromide was found to be the method of choice for regioselective and stereoconservative preparation of a 2â²-monoarylated precursor suitable for further functionalization at position 2.
Journal: Tetrahedron Letters - Volume 52, Issue 41, 12 October 2011, Pages 5379-5383