中国科技论文在线

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2007年10月24日

【期刊论文】Synthesis of some new chiral bifunctional o-hydroxyarylphosphonodiamides and their application as ligands in Ti(IV) complex catalyzed asymmetric silylcyanation of aromatic aldehydes

周正洪， Ke He， Zhenghong Zhou， Lixin Wang， Kangying Li， Guofeng Zhao， Qilin Zhou and Chuchi Tang

Tetrahedron 60 (2004) 10505-10513，-0001，（）：

-1年11月30日

摘要

Some new chiral bifunctional o-hydroxyarylphosphonodiamides were synthesized starting from (+)-cis-1,2,2-trimethylcyclopentane-1,3-diamine and the absolute configuration of the phosphorus atom was determined by X-ray diffraction analysis. Excellent enantioselectivity (up to 98% ee) was achieved in asymmetric silylcyanation of aromatic aldehydes using a chiral titanium complex formed in situ from Ti(OiPr)4 and o-hydroxyarylphosphonodiamide as the catalyst.

Chiral cyclophosphonodiamide， Asymmetric silylcyanation， Catalysis， Enantioselectivity， Aromatic aldehyde

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2007年10月24日

【期刊论文】Synthesis of a novel chiral Schiff base of (R,R)-11,12-diamino-9,10-dihydro-9,10-ethanonanthracene and its application as ligand in Ti(IV) complex catalyzed asymmetric silylcyanation of aldehydes

周正洪， Zebing Zeng， Guofeng Zhao， Peng Gao， Hongying Tang， Bo Chen， Zhenghong Zhou， Chuchi Tang

Catalysis Communications 8 (2007) 1443-1446，-0001，（）：

-1年11月30日

摘要

A novel chiral salen ligand (R,R)-2 was synthesized through the condensation of (R,R)-11,12-diamino-9,10-dihydro-9,10-ethanoanthracene and 3,5-di-tert-butylsalicylaldehyde. The (salen)Ti(IV) complex formed in situ upon the treatment of ligand 2 and Ti(OPr-i)4 was proved to be an efficient catalyst for the asymmetric trimethylsilylcyanation of aldehydes. The corresponding cyanohydrins were obtained in high yields (75-97%) with moderate to good enantioselectivities (48-76%).

Chiral (， salen)， Ti(， IV)， complex， Asymmetric silylcyanation， Enantioselectivity， Aldehydes

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2007年10月24日

【期刊论文】Synthesis of some new chiral cyclic o-hydroxylarylphosphonodiamides as ligands for asymmetric silylcyanation of aromatic aldehydes

周正洪， Zhuohong Yang， Zhenghong Zhou， Ke He， Lixin Wang， Guofeng Zhao， Qilin Zhou and Chuchi Tang

Tetrahedron: Asymmetry 14 (2003) 3937-3941，-0001，（）：

-1年11月30日

摘要

Some new chiral cyclic o-hydroxylarylphosphonodiamides were synthesized from (−)-α-phenylethylamine and found to be efficient ligands for the Ti(OPr-i )4 catalyzed asymmetric trimethylsilylcyanation of aromatic aldehydes. Corresponding cyanohydrins were obtained in good chemical yield and enantiomeric excesses up to 90%.

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2007年10月24日

【期刊论文】Synthesis of Optically Active α,β-Unsaturated Triazolyl Alcohols via Chiral Auxiliary-Modified NaBH4 Reduction of the Corresponding Ketones

周正洪， Zhou Zhenghong， Tang Yilong， Wang Lixin， Zhao Guofeng， Zhou Qilin， Tang Chuchi

SYNTHESIS 2004, No. 2, pp. 0217-0220，-0001，（）：

-1年11月30日

摘要

α-Disubstituted pyrrolidine-2-methanols were synthesized starting from L-proline and their application as chiral auxiliary in the asymmetric NaBH4 reduction of α,β-unsaturated triazolyl ketones was investigated. The corresponding α,β-unsaturated triazolyl alcohol derivatives (Uniconazole and Diniconazole) were obtained in good chemical yields with high ee values (up to 93%).

triazoles， L-proline， asymmetric reduction

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2007年10月24日

【期刊论文】The Aza-Morita–Baylis–Hillman Reaction of N-Thiophosphoryl Imines Catalyzed by 1,3,5-Triaza-7-phosphaadamantane (PTA) –– Convenient Synthesis of α-Methylene-β-Amino Ketone or Acid Derivatives

周正洪， Xinyuan Xu， Chungui Wang， Zhenghong Zhou， Xiaofang Tang， Zhengjie He， and Chuchi Tang

Eur. J. Org. Chem. 2007, 4487-4491，-0001，（）：

-1年11月30日

摘要

In the presence of an effective air-stable nucleophilic trialkylphosphane orgaocatalyst, 1,3,5-triaza-7-phosphaadamantane, N-diethoxythiophosphorylimines 1 and N-diphenylthiophosphinoylimines 2 exhibited good reactivity in the methyl vinyl ketone or methyl acrylate based aza-Morita–Baylis–Hillman reaction. The corresponding products were obtained in fair-to-excellent chemical yields. Moreover, the chiral-imine-induced diastereoselective aza-MBH reaction was also realized with 90% de. This reaction provides a convenient method for the synthesis of synthetically valuable α-methylene-β-amino ketone or acid derivatives.

Imines， Alkenes， Aza-Morita–Baylis–Hillman reaction， Ketones

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