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Studies Toward Organic Ion Pair-based Asymmetric Addition Reactions

Posted on:2016-07-02Degree:MasterType:Thesis
Country:ChinaCandidate:L Y BaoFull Text:PDF
GTID:2191330479490284Subject:Organic Chemistry
Abstract/Summary:PDF Full Text Request
Asymmetric catalysis of chiral quaternary phosphonium salts, which is one of the important protocols of chiral phase transfer catalysis, has increasingl y attracted significant attention of organic chemists in recent years due to their successful utilization to asymmetrically synthesize β-nitro alcohols, β-nitro amines, α-hydroxyphosphonic acid derivatives, and all(hetero) quaternary carbon compounds. The chiral sources of the cation moieties, as known as the core skeletons of the asymmetrical induction units in the salt catalysts, are the foundation for building chiral environment. Currently the representative skeletons mainly derivative from the axially chiral 1,1’-bi-2-naphthol, chiral ethylenediamines and chiral amino acids. In this dissertation, with starting from the related axially chiral diamines, the synthesis of the 6, 6’-diaryl substituted 1,1′-spirobiindane-7,7′-diamines and 3,3’-diaryl substituted H8 naphthylamines has been explored, and the corresponding quaternary phosphonium salt catalysts were prepared. Subsequently, the resulted catalysts were applied to investig ate the asymmetric additions.The racemic 1,1′-spirobiindane-7,7′-diol(SPINIOL) was synthesized via 6 steps from the acetone and 3-methoxybenzaldehyde. Subsequently, the inclusion resolution method was employed to obtain the optically pure SPINOL with ut ilizing the N-benzylcinchonidinium chloride as the resolution reagent, followed by the prepararion of the enantiopure 1,1′-spirobiindane-,7′-diamine(SPINAM) via convertion to-OTf group 、 Buchwald-Hartwig cross coupling and reductive debenzylation. Furthermore, four approaches to convert substituted axially chiral diols to substituted axially chiral diamines have been tried according to the retrosynthetic analysis. Simultaneously,the substituted H8 naphthylamines were prepared from naphthylamine via reductive hydrogenation、ortho bromination and Suzuki cross coupling.A quarternary phosphonium salt catalyst was prepared from the SPINAM and has been applied to asymmetrically catalyze the addition reactions with good chemical yields, namely the Pudovik addition of aromatic aldimine with diethyl phosphite and the Michael addition of chalcone with malononitrile, which have not been mediated by the same styles of catalysts until now.In this dissertation, one new catalyst was prepared and applied to asymmetrically catalyze two addition reactions, which laid a foundation for enriching the skeleton types of the quaternary phosphonium salts and seeking to construct more effecient catalysts.
Keywords/Search Tags:Chiral quaternary phosphonium salts, Axially chiral diamine, Retrosynthetic analysis, Asymmetric phase-transfer catalysis
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