Copper(I) Complexes of P ‐Stereogenic Josiphos and Related Ligands
نویسندگان
چکیده
Starting from (R)-Ugi's amine, diastereoselective lithiation followed by Ar'PCl2 and then Ar’’MgBr led to the generation, as single diastereoisomers, of (R,Sp,Sphos) [Ar’=Ph, Ar’’=o-Tol] (R,Sp,Rphos) [Ar’=o-Tol, Ar’’=Ph] PPFA ligand derivatives. Amine substitution both with HPCy2 gave P-stereogenic Josiphos ligands, addition CuCl, corresponding copper(I) complexes. The latter were also generated using borane P N protecting groups in situ Cu(I) complexation, avoiding isolation air-sensitive phosphine intermediates. This protection methodology was applied synthesis Josiphos/CuCl complexes derived PCl3. In addition, related bulky cobalt-sandwich complex-based derivatives obtained. Preliminary investigation revealed isolated CuCl competent catalyst precursors for enantioselective conjugate reactions.
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ژورنال
عنوان ژورنال: European Journal of Organic Chemistry
سال: 2021
ISSN: ['1434-193X', '1099-0690']
DOI: https://doi.org/10.1002/ejoc.202100146