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Ni(CO) 4 + P-P (PP)Ni(CO) 2 + 2 CO. BITIOP. DPPB R=H. (DPPB)Ni(CO) 2. (BITIOP)Ni(CO) 2. R,R. Pd(PhCN) 2 Cl 2. Ni(CO) 4. b '. a. b. a '. Cs. -38.98 ppm. -1.75 ppm. b. a. H 2. H 2. H 2. e.d.% = 43% e.e.% = 70% Conf = R/R. Conv % = 100% (55h)
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Ni(CO)4 + P-P (PP)Ni(CO)2 + 2 CO BITIOP DPPB R=H (DPPB)Ni(CO)2 (BITIOP)Ni(CO)2 R,R Pd(PhCN)2Cl2 Ni(CO)4 b' a b a' Cs -38.98 ppm -1.75 ppm b a H2 H2 H2 e.d.% = 43% e.e.% = 70% Conf = R/R Conv % = 100% (55h) e.e. % = 66% (Ar = C6H5) e.e. % = 64% (Ar = C8H9) Conf = R conv (%) = 100% α+β/l = 60/40 α/β = 67/33 lin Structural variations on chiral ligands: new chelanting diphosphines from optical active (1,4)-(Z)-2-butenes. E. Cesarotti, I. Rimoldi, P. Spalluto Università degli Studi di Milano, Facoltà di Farmacia, Dipartimento di Chimica Inorganica, Metallorganica e Analitica. Another essential feature: the modulation of the ligand steric properties by the modification of the substituents on the stereogenic atoms versus An essential feature: the conformational rigidity of the ligand Is it possible to prepare a ligand gathering the conformational rigidity of an atropisomeric ligand with the possibility to modulate steric properties by the modification of the substituents on the stereogenic atoms? TsCl NaOH enzymatic resolution by LAK Vinyl acetate Commercial available mixture S,S S,S Ar2PLi -78°C S,S e.e.% > 98% meso R,R Work in progress: R=(CH3)2CH-, C6H11-, C6H5-