Font Size

SCREEN

Layout

Cpanel

26September2017

Prof. Qi-Lin Zhou's Research Group

周其林教授课题组主页

Highlights

1.  Development of privileged chiral spiro ligands and catalysts

     Although a great number of chiral ligands as well as chiral catalysts have been reported in the past decades, only a handful of them rooted on a very few core structures can be regarded as truly successful as they demonstrate proficiency in a variety of mechanistically unrelated reactions. People named the chiral catalysts showing good enantioselectivity over a wide range of different reactions "privileged chiral catalysts", term coined by Jacobsen. The essential thing makes one catalyst to be "privileged" is the scaffold (core structure) it possessed. Chiral 1,1'-spirobiindane scaffold collect high rigidity, perfect C2 symmetric, simple chirality, and easy modification and represents one of the ideal chiral ligand backbones. Starting with easily available 1,1'-spirobiindane-7,7'-diol (SPINOL), more than one hundred chiral spiro ligands including diphosphines SDPs, bisoxazolines SpiroBOXs, amino-phosphines SpiroAP, phosphine-oxazolines SIPHOXs, diimines SIDIMs, and a wide range of monodentate phosphorous ligands SITCPs, ShiPs, FuPs, and SIPHOS, have been prepared through a single or multiple steps. Some of these ligands, such as SIPHOS, ShiPs, SDPs, SIPHOXs, and SpiroBOXs are now commercially available from Aldrich and Strem Co. The chiral spiro ligands have been applied in a variety of mechanistically unrelated reactions, such as hydrogenation, carbon–carbon bond formation, and carbon–heteroatom bond formation, and exhibit unique enantioselectivity and reactivity. The chiral spiro ligands have become one of the "privileged" chiral ligands.


 2.  Asymmetric hydrogenation

     The transition metal-catalyzed asymmetric hydrogenation utilizing molecular hydrogen to reduce prochiral unsaturated bonds is one of the most efficient and atom-economic methods for the preparation of optically active compounds. The chiral spiro ligands including bidentate phosphines SDPs, phosphine-oxazolines SIPHOXs, amino-phosphines SpiroAP, and monodentate phosphorous ligands (SIPHOS and FuPs) exhibited high activity and excellent enantioselectivity in the asymmetric hydrogenations of functionalized olefins (including enamides, enamines, and α,β-unsaturated carboxylic acids), ketones, aldehydes, and imines.

2.1  Hydrogenation of enamides

 Ref. Chem. Commun. 2002, 480–481. 
        Angew. Chem. Int. Ed. 200241, 2348–2350.
        J. Org. Chem200469, 4648–4655.
        J. Org. Chem200469, 8157–8160.

2.2  Hydrogenation of enamines

Ref. J. Am. Chem. Soc. 2006128, 11774–11775.
       J. Am. Chem. Soc. 2009131, 1366–1367.
       Adv. Synth. Catal2009351, 3243–3250.

2.3   Hydrogenation of α,β-unsaturated acids

Ref. J. Am. Chem. Soc. 2008, 130, 8584–8585.
       J. Am. Chem. Soc. 2010, 132, 1172–1179.

2.4   Hydrogenation of ketones

 Ref. J. Am. Chem. Soc. 2003125, 4404–4405.
        J. Am. Chem. Soc. 2010132, 4538–4539.

2.5   Hydrogenation of racemic α-substituted aldehydes and ketones via DKR 

Ref. J. Org. Chem. 200570, 2967–2973.
       J. Am. Chem. Soc. 2007129, 1868–1869. 
       Angew. Chem. Int. Ed. 200746, 7506–7508.
       J. Am. Chem. Soc. 2009131, 4222–4223.
       Adv. Synth. Catal. 2010352, 81–84.

2.6   Hydrogenation of imines

Ref. J. Am. Chem. Soc. 2006128, 12886–12891.


 3.   Asymmetric carbon-carbon bond-forming reaction

       Transition metal-catalyzed asymmetric carbon-carbon bond-forming reaction is essential in modern organic synthesis. Chiral spiro monodentate and bidentate phosphorous ligands have been successfully used in various asymmetric carbon-carbon bond-forming reactions. In most of investigated reactions, the spiro ligands showed superior chiral inducements than the ligands with other backbones.

3.1   Rhodium-catalyzed asymmetric arylation reactions

Ref. Org. Lett. 2006, 8, 1479–1481.
        Org. Lett. 2006, 8, 2567–2569.
        Angew. Chem. Int. Ed. 2008, 47, 4351–4353.


 3.2 Nickel-catalyzed three component coupling reaction


Ref. J. Am. Chem. Soc. 2007, 129, 2248–2249.
        J. Am. Chem. Soc. 2008, 130, 14052–14053.
        J. Am. Chem. Soc. 2010, 132, 10955–10957.

3.3    Nickel-catalyzed hydrovinylation reaction

Ref. J. Am. Chem. Soc. 2006, 128, 2780–2781. 

3.4   Rhodium-catalyzed hydrosilylation/cyclization reaction

 Ref. Angew. Chem. Int. Ed. 200746, 1275–1277.


 4.  Asymmetric carbon-heteroatom bond-forming reaction

      Because carbon–heteroatom (C–X) bonds are prevalent in organic compounds, the development of reliable and efficient methods for construction of such bonds is of highly practical value. Transition metal–catalyzed insertion of carbenes into heteroatom–hydrogen bonds (X–H, X = O, N, S, etc.) provides one of the most efficient approaches to the formation of C–X bonds. Remarkable advances have been made in the development of methodology for catalytic asymmetric diazo insertion into C–H bonds, but only limited success has been achieved for asymmetric diazo insertions into heteroatom–hydrogen bonds. By using chiral spiro bisoxazoline ligands SpiroBOXs and diimine ligands SIDIMs, a series of catalytic asymmetric insertion of α-diazoesters into N–H, O–H, S–H, and Si–H bonds was developed with high to excellent enantioselectivities. 

Ref. J. Am. Chem. Soc. 2007129, 5834–5835.
       J. Am. Chem. Soc. 2007, 129, 12616–12617.
       Angew. Chem. Int. Ed. 2008, 47, 932–934.
       Angew. Chem. Int. Ed. 2008, 47, 8496–8498.
       Nature Chemistry. 2010, 2, 546−551.


 5. Asymmetric synthesis of biologically active compounds

     Various aforementioned catalytic procedures have been applied in the synthesis of biologically active compounds and natural products.

5.1   Synthesis of key intermediate of new blood pressure-lowering drug Aliskiren

Ref. J. Am. Chem. Soc. 2008, 130, 8584–8585.

5.2   Synthesis of key intermediate of rupintrivir, a rhinovirus protease inhibitor

Ref. J. Am. Chem. Soc. 2010, 132, 1172–1179.

5.3   Synthesis of key intermediate of active form of the anti-inflammatory loxoprofen.

Ref. J. Am. Chem. Soc. 2010, 132, 4538–4539.

5.4   Synthesis of leukotriene receptor antagonists BAY X 1005

Ref. J. Am. Chem. Soc. 2007, 129, 1868–1869.

5.5   Synthesis of highly selective κ-opioid agonist U-(-)-50488

Ref. Angew. Chem. Int. Ed. 2007, 46, 7506–7508.

5.6   Synthesis of isoquinoline alkaloid crispine A 
 

Ref. J. Am. Chem. Soc. 2009, 131, 1366–1367.

5.7    Synthesis of natural product α- and β-conhydrine

Ref. Org. Lett. 2009, 11, 4994–4997.