Design,Synthesis And Application Of Novel Hex-Amethyl-1,1'-spirobiindane-based Chiral Biphosphine Ligands

Chiral diphosphine ligands occupy a significant position in asymmetric catalysis,among which diphosphine ligands bearing spirobiindane scaffold have been recogniz ed as one of the most dominant ligands due to their strong rigidity and skeleton stabili ty.This dissertation firstly reviewed the research progress and applications in asymme tric reactions of diphosphine ligands.Then,a novel series of hexamethyl-1,1'-spirobii ndane-derived diphosphine(HMSI-PHOS)ligands have been designed and synthesized.Finally,the Pd-complex of the new ligands has been successfully applied to the asymmetric allylation to prove their catalytic activity and enantioselectivity.The details were summarized as following:The chiral hexamethyl spiro diphosphine(HMSI-PHOS)ligands were synthesize d from commercially available bisphenol C(BPC)in industry by five steps of cyclizat ion,bromination,esterification,reduction and substitution with a total yield of 25.1%-33.5%.All the seven synthetic ligands were characterized by 1H-NMR,13C-NMR,31P-NMR,GC-TOF,IR and optical rotation.The chiral resolving reagent(S)-naproxen chloride was successfully applied to the chiral resolution of the key intermediate hexamethyl spiro dibromo-diol,and the absolute configuration was confirmed by X-ray crystallographic analysis of a single crystal.Meanwhile,seven chiral hexamethyl spiromonophosphine ligands,seven chiral hexamethyl spiro dioxyphosphine compounds and seven chiral hexamethyl monooxy phosphine compounds were obtained and characterized during the research.A highly enantioselective allylation reaction catalyzed by Pd/HMSI-PHOS was developed.Under the optimal reaction conditions of 7 mol%2.6a,3 mol%[Pd(C3H5)Cl]2,and diethylzinc in toluene at-20 ?,twenty one optically active 1,3-diaryl-2-allylmalonate derivatives were synthesized in high yields(up to 96%)with good enantioselectivities(up to 87%)from 1,3-diaryl-2-allyl acetate and dialkyl malonate or diaryl malonate after the screening of the ligands,metalprecursors,solvents,temperature,and base.