Blue Light Photocatalytic Glycosylation without Electrophilic Additives.

Photocatalytic formation of glycosidic bonds employing stable and readily accessible O-glycosyl derivatives of 2,2,6,6-tetramethylpiperidin-1-ol is presented that employs an iridium-based photocatalyst and blue LEDs. The reaction proceeds at room temperature and in the absence of additives other than 4 Å molecular sieves. Stereoselectivities are modest but nevertheless dependent on the anomeric configuration of the donor, suggesting a substantial degree of concerted character.

[1]  Eugene E. Kwan,et al.  Sensitive and Accurate 13C Kinetic Isotope Effect Measurements Enabled by Polarization Transfer. , 2017, Journal of the American Chemical Society.

[2]  H. Overkleeft,et al.  Mapping the Reactivity and Selectivity of 2-Azidofucosyl Donors for the Assembly of N-Acetylfucosamine-Containing Bacterial Oligosaccharides , 2017, The Journal of organic chemistry.

[3]  H. Overkleeft,et al.  The influence of acceptor nucleophilicity on the glycosylation reaction mechanism† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc04638j Click here for additional data file. , 2016, Chemical science.

[4]  Mark S. Taylor,et al.  Borinic Acid Catalyzed Stereo- and Regioselective Couplings of Glycosyl Methanesulfonates. , 2016, Journal of the American Chemical Society.

[5]  Emily C. Gentry,et al.  Catalytic Carbocation Generation Enabled by the Mesolytic Cleavage of Alkoxyamine Radical Cations. , 2016, Angewandte Chemie.

[6]  D. Takahashi,et al.  Stereocontrolled Photoinduced Glycosylation Using an Aryl Thiourea as an Organo photoacid. , 2016, Organic letters.

[7]  De‐Cai Xiong,et al.  Visible Light Photoredox-Catalyzed O-Sialylation Using Thiosialoside Donors. , 2016, The Journal of organic chemistry.

[8]  De‐Cai Xiong,et al.  Light-driven highly efficient glycosylation reactions , 2016 .

[9]  Revati Kumar,et al.  A Visible-Light-Promoted O-Glycosylation with a Thioglycoside Donor. , 2016, Angewandte Chemie.

[10]  D. Crich,et al.  Carbohydrate reactivity: Glycosyl cations out on parole. , 2016, Nature chemistry.

[11]  A. Ardá,et al.  Catching elusive glycosyl cations in a condensed phase with HF/SbF₅ superacid. , 2016, Nature chemistry.

[12]  Grace A. Winschel,et al.  Studies of the Mechanism and Origins of Enantioselectivity for the Chiral Phosphoric Acid-Catalyzed Stereoselective Spiroketalization Reactions. , 2016, Journal of the American Chemical Society.

[13]  De‐Cai Xiong,et al.  Photoinduced C-S Bond Cleavage of Thioglycosides and Glycosylation. , 2015, Organic letters.

[14]  P. Retailleau,et al.  Cation Clock Reactions for the Determination of Relative Reaction Kinetics in Glycosylation Reactions: Applications to Gluco- and Mannopyranosyl Sulfoxide and Trichloroacetimidate Type Donors. , 2015, Journal of the American Chemical Society.

[15]  T. Rosenau,et al.  Theoretical study on the effects of a 4,6-O-diacetal protecting group on the stability of ion pairs from D-mannopyranosyl and D-glucopyranosyl triflates. , 2015, Carbohydrate research.

[16]  D. Crich,et al.  A propos of glycosyl cations and the mechanism of chemical glycosylation; the current state of the art. , 2015, Carbohydrate research.

[17]  T. Rosenau,et al.  Theoretical foundation for the presence of oxacarbenium ions in chemical glycoside synthesis. , 2014, The Journal of organic chemistry.

[18]  D. Takahashi,et al.  Photo-induced glycosylation using reusable organophotoacids. , 2014, Chemical communications.

[19]  Takayuki Kato,et al.  Probing the Influence of Protecting Groups on the Anomeric Equilibrium in Sialic Acid Glycosides with the Persistent Radical Effect , 2014, Journal of the American Chemical Society.

[20]  A. Demchenko,et al.  A study of silver (I) perchlorate as an effective promoter for chemical glycosylation with thioimidates and thioglycosides , 2014 .

[21]  Weihua Xue,et al.  Photocatalytic Synthesis of Glycosyl Bromides , 2014 .

[22]  D. Takahashi,et al.  Light-induced O-glycosylation of unprotected deoxythioglycosyl donors. , 2013, Organic & biomolecular chemistry.

[23]  Xiaoping Wang,et al.  An α-selective, visible light photocatalytic glycosylation of alcohols with selenoglycosides. , 2013, Carbohydrate research.

[24]  A. Bowers,et al.  Visible light mediated activation and O-glycosylation of thioglycosides. , 2013, Organic letters.

[25]  P. Retailleau,et al.  Cation clock permits distinction between the mechanisms of α- and β-O- and β-C-glycosylation in the mannopyranose series: evidence for the existence of a mannopyranosyl oxocarbenium ion. , 2012, Journal of the American Chemical Society.

[26]  D. Pratt,et al.  Dissecting the Mechanisms of a Class of Chemical Glycosylation Using Primary 13C Kinetic Isotope Effects , 2012, Nature Chemistry.

[27]  D. Crich,et al.  Photoinitiated Glycosylation at 350 nm , 2011 .

[28]  Derek S. Tan,et al.  Hydrogen-bonding catalysis and inhibition by simple solvents in the stereoselective kinetic epoxide-opening spirocyclization of glycal epoxides to form spiroketals. , 2011, Journal of the American Chemical Society.

[29]  Xue‐Wei Liu,et al.  Direct C-glycosylation of organotrifluoroborates with glycosyl fluorides and its application to the total synthesis of (+)-varitriol. , 2011, Organic letters.

[30]  D. Crich.  Mechanism of a chemical glycosylation reaction. , 2010, Accounts of chemical research.

[31]  Matthew G. Beaver,et al.  Erosion of stereochemical control with increasing nucleophilicity: O-glycosylation at the diffusion limit. , 2010, The Journal of organic chemistry.

[32]  K. Woerpel,et al.  Correlations between nucleophilicities and selectivities in the substitutions of tetrahydropyran acetals. , 2009, The Journal of organic chemistry.

[33]  C. Uriel,et al.  IPy2BF4/HF-pyridine: a new combination of reagents for the transformation of partially unprotected thioglycosides and n-pentenyl glycosides to glycosyl fluorides. , 2007, The Journal of organic chemistry.

[34]  C. Uriel,et al.  IPy2BF4-mediated transformation of n-pentenyl glycosides to glycosyl fluorides: a new pair of semiorthogonal glycosyl donors. , 2007, Organic letters.

[35]  R. Field,et al.  Practical de-O-acylation reactions promoted by molecular sieves. , 2004, Carbohydrate research.

[36]  H. Kamada,et al.  Novel glycosylation of the nitroxyl radicals with peracetylated glycosyl fluorides using a combination of BF(3) x OEt(2) and an amine base as promoters. , 2001, Carbohydrate research.

[37]  Steven V. Ley,et al.  Tuning glycoside reactivity: New tool for efficient oligosaccharide synthesis , 1998 .

[38]  K. Takeuchi,et al.  Activation of selenoglycosides by photoinduced electron transfer , 1996 .

[39]  M. A. Clarke,et al.  Photoinduced generation of glucosyl cations from thioglycosides , 1990 .

[40]  P. Konradsson,et al.  Armed and disarmed n-pentenyl glycosides in saccharide couplings leading to oligosaccharides , 1988 .

[41]  R. Noyori,et al.  Novel nucleophilic substitution reaction by radical cation intermediates. Photosensitized transacetalization via SON1 mechanism , 1985 .

[42]  M. Hayashi,et al.  Simple synthesis of glycosyl fluorides , 1984 .

[43]  J. B. Lambert,et al.  INCREASED ELECTRON DEMAND IN THE SOLVOLYSIS OF SECONDARY 2-NORBORNYL TOSYLATES , 1978 .

[44]  C. Glaudemans,et al.  Long-Range Effects of Acyl Groups in the Solvolysis of Glycofuranosyl Halides. The Synthesis of 2,3-Di-O-benzyl-5-O-p-nitrobenzoyl-α-D- arabinofuranosyl Chloride and of 2-O-Benzyl- 3,5-di-O-p-nitrobenzoyl-α-D-arabinofuranosyl Chloride , 1965 .