81447-34-9Relevant academic research and scientific papers
General Method for the Preparation of Electron-Deficient Imidazo[1,2-a]pyridines and Related Heterocycles
McDonald, Ivar M.,Peese, Kevin M.
supporting information, p. 6002 - 6005 (2016/01/09)
A new annulation method for the preparation of the imidazo[1,2-a]pyridine ring system under mild conditions is presented. Treatment of a 2-aminopyridine with a dimethylketal tosylate in acetonitrile at elevated temperature (80-140°C) in the presence of catalytic Sc(OTf)3 provides the imidazo[1,2-a]pyridine product in good yield. The annulation method is broadly applicable to electron-poor 2-aminopyridines and displays a complementary profile to the classic preparation of the imidazo[1,2-a]pyridine ring system by reaction of a bromoketone with electron-rich and -neutral substrates. The scope of the process and mechanistic considerations are discussed.
Enantioselective Iodine(III)-Mediated Synthesis of α-Tosyloxy Ketones: Breaking the Selectivity Barrier
Basdevant, Benoit,Legault, Claude Y.
supporting information, p. 4918 - 4921 (2015/10/12)
The development of practical methods to access chiral nonracemic α-substituted ketones is of particular importance due to their ubiquitous nature. Unprecedented levels of enantioselectivity are reported for the synthesis of α-tosyloxy ketones, using enol esters and chiral iodine(III) reagents. The reaction can be performed under both stoichiometric and catalytic conditions. These results suggest widely different reaction mechanisms for the reaction of ketones versus enol esters, supporting recent computational insights.
Study of the Reactivity of [Hydroxy(tosyloxy)iodo]benzene Toward Enol Esters to Access α-Tosyloxy Ketones
Basdevant, Benoit,Legault, Claude Y.
, p. 6897 - 6902 (2015/10/06)
The reactivity of enol esters toward [hydroxy(tosyloxy)iodo]benzene (HTIB) was assessed. These substrates were found to be rapidly converted in high yields to their corresponding α-tosyloxy ketones. This transformation demonstrates that these substrates can act as ketone surrogates. The scope of the method was investigated and aromatic, aliphatic, and cyclic enol esters were found to be suitable substrates for the reaction. The relative reactivity of a model substrate toward HTIB and m-CPBA was investigated, and it was found that the reaction could be performed under catalytic conditions.
2,4,6-Tris(4-iodophenoxy)-1,3,5-triazine as a new recyclable "iodoarene" for in situ generation of hypervalent iodine(III) reagent for α-tosyloxylation of enolizable ketones
Thorat, Prerana B.,Bhong, Bhagyashree Y.,Shelke, Amol V.,Karade, Nandkishor N.
, p. 3332 - 3335 (2014/06/09)
The synthesis of 2,4,6-tris[(4-iodo)phenoxy)]-1,3,5-triazine 6, as a new recyclable nonpolymeric analogue of iodobenzene is achieved using the reaction of 2,4,6-trichloro-1,3,5-triazine with 4-iodophenol in the presence of KOH. The application of 6 as a r
One-Pot Protocol for Synthesis of -Organosulfonyloxy Ketones from Secondary Alcohols Using Hypervalent Iodine(V)-Mediated Oxidations
Deshmukh, Swapnil S.,Huddar, Sameerana N.,Akamanchi, Krishnacharya G.
experimental part, p. 3101 - 3110 (2009/11/30)
Tosyloxy ketones and -mesyloxy ketones were directly prepared from alcohols in one pot by treatment with hypervalent iodine(V) reagents in combination with p-toluenesulfonic acid and methanesulfonic acid, respectively, in moderate to good yields. Reaction
M-iodosylbenzoic acid: Recyclable hypervalent iodine reagent for-tosyloxylation and-mesyloxylation of ketones
Yusubov, Mekhman S.,Funk, Tatyana V.,Yusubova, Roza Y.,Zholobova, Galina,Kirschning, Andreas,Park, Joo Yeon,Chi, Ki-Whan
experimental part, p. 3772 - 3784 (2009/12/06)
m-Iodosylbenzoic acid-mediated reactions of various carbonyl compounds provided-organosulfonyloxy carbonyl compounds in good yields. The final products could be easily isolated without any chromatographic purification by simple treatment of the crude mixt
Solvent-free synthesis of 1-(p-toluenesulfonyloxy)-1,2-benziodoxol-3(1H)-one from Dess-Martin periodinane and its synthetic utility for α-tosyloxylation of ketones
Karade, Nandkishor N.,Tiwari, Girdharilal B.,Shinde, Sandeep V.,Gampawar, Sumeet V.,Kondre, Jeevan M.
, p. 3441 - 3443 (2008/09/21)
The solvent-free synthesis of 1-(p-toluenesulfonyloxy)-1,2-benziodoxol-3(1H)-one is reported from Dess-Martin periodinane and p-toluenesulfonic acid monohydrate using a grinding technique and is subsequently utilized for the α-tosyloxylation of a range of enolisable ketones.
A new application of hypervalent iodine (λ5) reagents with organosulfonic acids for direct α-organosulfonyloxylation carbonyl compounds
Mahajan, Ulhas S.,Akamanchi, Krishnacharya G.
experimental part, p. 987 - 990 (2009/04/04)
Hypervalent iodine (λ5) reagents in combination with p-toluenesulfonic acid when reacted with ketones under reflux temperature in acetonitrile gave α-tosyloxy ketones in moderate to excellent yields. The reaction was developed further for both
Direct α-oxytosylation of carbonyl compounds: One-pot synthesis of heterocycles
John, Oliver R. S.,Killeen, Niall M.,Knowles, Deborah A.,Yau, Sze Chak,Bagley, Mark C.,Tomkinson, Nicholas C. O.
, p. 4009 - 4012 (2008/02/11)
N-Methyl-O-tosylhydroxylamine is an effective reagent for the direct α-oxytosylation of carbonyl compounds. The reactions proceed smoothly at room temperature in the presence of both moisture and air and functional group tolerance in the substrate is good. With nonsymmetrical substrates regioselectivity for primary over secondary centers is observed and complete regiospecificity for primary over tertiary centers is obtained. Addition of a bis-heteronucleophile directly to the crude reaction mixture in a one-pot process leads to the corresponding heterocyclic product.
[Hydroxy(tosyloxy)iodo]benzene mediated α-azidation of ketones
Prakash, Om,Pannu, Kamaljeet,Prakash, Richa,Batra, Anita
, p. 523 - 527 (2007/10/03)
Reaction of various ketones with [hydroxy(tosyloxy)iodo]benzene (HTIB) followed by treatment of the α-tosyloxy ketones thus generated in situ with NaN3 offers a one-pot procedure for the synthesis of α-azido ketones. The HTIB used in this conversion may also be generated in situ by using iodosobenzene in combination with p-toluene-sulphonic acid.
