1
|
Synthesis of new Tetrazole based-semiconducting polymers for optoelectronic application: Study of the effect of anthracene group on photophysical properties. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.131760] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
2
|
He Q, Ye JL, Xu FF, Geng H, Chen TT, Chen H, Huang PQ. Tf 2O/TTBP (2,4,6-Tri- tert-butylpyrimidine): An Alternative Amide Activation System for the Direct Transformations of Both Tertiary and Secondary Amides. J Org Chem 2021; 86:16300-16314. [PMID: 34499513 DOI: 10.1021/acs.joc.1c01572] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Ten types of Tf2O/TTBP-mediated amide transformation reactions were investigated. The results showed that compared with pyridine derivatives 2,6-di-tert-butyl-4-methylpyridine (DTBMP) and 2-fluoropyridine (2-F-Pyr.), TTBP can serve as an alternative amide activation system for the direct transformation of both secondary and tertiary amides. For most surveyed examples, higher or comparable yields were generally obtained. In addition, Tf2O/TTBP combination was used to promote the condensation reactions of 2-(tert-butyldimethylsilyloxy)furan (TBSOF) with both tertiary and secondary amides, the one-pot reductive Bischler-Napieralski-type reaction of tertiary lactams, and Movassaghi and Hill's modern version of the Bischler-Napieralski reaction. The value of the Tf2O/TTBP-based methodology was further demonstrated by the concise and high-yielding syntheses of several natural products.
Collapse
Affiliation(s)
- Qian He
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| | - Jian-Liang Ye
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| | - Fang-Fang Xu
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| | - Hui Geng
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| | - Ting-Ting Chen
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| | - Hang Chen
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| | - Pei-Qiang Huang
- Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, P. R. China
| |
Collapse
|
3
|
Mukherji A, Kancharla PK. C–H···Anion Interactions Assisted Addition of Water to Glycals by Sterically Hindered 2,4,6-Tri-tert-butylpyridinium Hydrochloride. Org Lett 2020; 22:2191-2195. [DOI: 10.1021/acs.orglett.0c00348] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ananya Mukherji
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Pavan K. Kancharla
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| |
Collapse
|
4
|
Ghosh T, Mukherji A, Kancharla PK. Sterically Hindered 2,4,6-Tri-tert-butylpyridinium Salts as Single Hydrogen Bond Donors for Highly Stereoselective Glycosylation Reactions of Glycals. Org Lett 2019; 21:3490-3495. [DOI: 10.1021/acs.orglett.9b00626] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Titli Ghosh
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Ananya Mukherji
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Pavan K. Kancharla
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| |
Collapse
|
5
|
Poulsen LT, Heuckendorff M, Jensen HH. On the generality of the superarmament of glycosyl donors. Org Biomol Chem 2018. [DOI: 10.1039/c7ob02966g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We establish that the electronic superarmament of 2-OBz thioglucoside glycosyl donors under NIS/TfOH activation is not a general phenomenon.
Collapse
|
6
|
Heuckendorff M, Bols PS, Barry CB, Frihed TG, Pedersen CM, Bols M. β-Mannosylation with 4,6-benzylidene protected mannosyl donors without preactivation. Chem Commun (Camb) 2015. [PMID: 26197760 DOI: 10.1039/c5cc04716a] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Mannosylations with benzylidene protected mannosyl donors were found to be β-selective even when no preactivation was performed. It was also found that the kinetic β-product in some cases anomerizes fast to the thermodynamically favored α-anomer under typical reaction conditions.
Collapse
Affiliation(s)
- Mads Heuckendorff
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark.
| | | | | | | | | | | |
Collapse
|
7
|
Yang L, Zhu J, Zheng XJ, Tai G, Ye XS. A highly α-stereoselective synthesis of oligosaccharide fragments of the Vi antigen from Salmonella typhi and their antigenic activities. Chemistry 2011; 17:14518-26. [PMID: 22095754 DOI: 10.1002/chem.201102615] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Indexed: 01/03/2023]
Abstract
In this paper, a convenient approach to the synthesis of the repeating α-(1→4)-linked N-acetyl galactosaminuronic acid units from the capsular polysaccharide of Salmonella typhi is reported. The exclusively α-stereoselective glycosylation reactions were achieved by using oxazolidinone-protected glycosides as building blocks based on a pre-activation protocol. Di-, tri-, and tetrasaccharides were prepared by this short and efficient approach in high yields. The enzyme-linked immunosorbent assay experiments show that our synthetic tri- and tetrasaccharide had much higher antigenic activities than previously reported ones in the inhibition of antibody binding by the native polysaccharide. The results demonstrate that the antigenic activities of saccharides can be strengthened greatly by increasing the number of acetyl groups present.
Collapse
Affiliation(s)
- Lin Yang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xue Yuan Road 38, Beijing 100191, China
| | | | | | | | | |
Collapse
|
8
|
Rasmussen CAH, van Der Plas HC. Aspects of the amination of 4-t-butyl-5-halogenopyrimidines by potassium amide in liquid ammonia. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19780971104] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
9
|
Kos NJ, van der Plas HC, van Veldhuizen A. The behaviour of 6- and 8-substituted purines toward potassium amide in liquid ammonia. A new example of tele
-amination. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19800990904] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
10
|
Yang L, Ye XS. A highly alpha-selective glycosylation for the convenient synthesis of repeating alpha-(1-->4)-linked N-acetyl-galactosamine units. Carbohydr Res 2010; 345:1713-21. [PMID: 20591420 DOI: 10.1016/j.carres.2010.05.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 05/24/2010] [Accepted: 05/31/2010] [Indexed: 11/24/2022]
Abstract
The repeating GalpNAc-alpha-(1-->4)-GalpNAc unit is part of a series of essential structures that can be found in many important biomolecules such as the glycoproteins and the O-antigenic polysaccharides of clinically important bacterial strains. In this paper, we describe an exclusive alpha-selective glycosylation reaction, using a 4,6-di-O-tert-butyldimethylsilyl-N-acetyloxazolidinone-protected thioglycoside as the glycosyl donor, under pre-activation conditions, with only half amount of the promoter, providing the product GalpNAc-alpha-(1-->4)-GalpNAc in high isolated yield. This reaction can be also applied to increasing the length of the repeating structure, which is of significant use in further synthesis of branched or linear oligosaccharides.
Collapse
Affiliation(s)
- Lin Yang
- State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Xue Yuan Road 38, Beijing 100191, China
| | | |
Collapse
|
11
|
Geng Y, Zhang LH, Ye XS. Stereoselectivity investigation on glycosylation of oxazolidinone protected 2-amino-2-deoxy-d-glucose donors based on pre-activation protocol. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.03.103] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
12
|
Geng Y, Zhang LH, Ye XS. Pre-activation protocol leading to highly stereoselectivity-controllable glycosylations of oxazolidinone protected glucosamines. Chem Commun (Camb) 2008:597-9. [DOI: 10.1039/b712591g] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
13
|
Saez R, Batanero B, Barba F. Influence of the concentration in the anodic oxidations of α-chloro-ethylbenzene or toluene in acetonitrile. Electrochem commun 2006. [DOI: 10.1016/j.elecom.2006.07.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
14
|
Kimball DB, Weakley TJR, Herges R, Haley MM. Deciphering the mechanistic dichotomy in the cyclization of 1-(2-ethynylphenyl)-3,3-dialkyltriazenes: competition between pericyclic and pseudocoarctate pathways. J Am Chem Soc 2002; 124:13463-73. [PMID: 12418899 DOI: 10.1021/ja027809r] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mechanistic aspects of the cyclization of (2-ethynylphenyl)triazenes under both thermal and copper-mediated conditions are reported. For cyclization to an isoindazole, a carbene mechanistic pathway is proposed. The carbene intermediate can react with oxygen, dimerize to give an alkene, or be trapped either intermolecularly (using 2,3-dimethyl-2-butene to generate a cyclopropane) or intramolecularly (using a biphenyl moiety at the terminus of the acetylene to form a fluorene). Density-functional theory (DFT) calculations support a pseudocoarctate pathway for this type of cyclization. Thermal cyclization to give a cinnoline from (2-ethynylphenyl)triazenes is proposed to occur through a pericyclic pathway. DFT calculations predict a zwitterionic dehydrocinnolinium intermediate that is supported by deuterium trapping studies as well as cyclizations performed using a 2,2,6,6-tetramethylpiperidine moiety at the 3-position of the triazene.
Collapse
Affiliation(s)
- David B Kimball
- Department of Chemistry, University of Oregon, Eugene 97403-1253, USA
| | | | | | | |
Collapse
|
15
|
Kimball DB, Weakley TJR, Haley MM. Cyclization of 1-(2-alkynylphenyl)-3,3-dialkyltriazenes: a convenient, high-yield synthesis of substituted cinnolines and isoindazoles. J Org Chem 2002; 67:6395-405. [PMID: 12201760 DOI: 10.1021/jo020229s] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new route to isoindazoles and cinnolines through the cyclization of (2-alkynylphenyl)triazenes under neutral conditions is presented. The products that result from heating the starting triazenes depend on both the type of alkyne ortho to the triazene functionality and the temperature used. Butadiyne moieties ortho to dialkyltriazenes yield bis-isoindazole dimers when heated to 150 degrees C in MeI. A requirement for cyclization in MeI is that the (2-alkynylphenyl)triazene must contain a suitably electron-withdrawing substituent on the phenyl ring to deactivate the triazene toward methylation-induced decomposition to an iodoarene. Ethynyl moieties ortho to dialkyltriazenes yield both isoindazole dimers as well as 3-formylisoindazoles when subjected to the same conditions. Replacing MeI with 1,2-dichlorobenzene as solvent allows for the general cyclization of (2-ethynylphenyl)dialkyltriazenes. Heating to 170 degrees C results in a mixture of isoindazole and cinnoline products, whereas the cinnolines are produced exclusively in high yield at 200 degrees C. Alternatively, the isoindazoles can be obtained in good to excellent yield by stirring a 1,2-dichloroethane solution of the starting triazene with CuCl overnight at 50 degrees C.
Collapse
Affiliation(s)
- David B Kimball
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403-1253, USA
| | | | | |
Collapse
|
16
|
Crich D, Smith M. 1-Benzenesulfinyl piperidine/trifluoromethanesulfonic anhydride: a potent combination of shelf-stable reagents for the low-temperature conversion of thioglycosides to glycosyl triflates and for the formation of diverse glycosidic linkages. J Am Chem Soc 2001; 123:9015-20. [PMID: 11552809 DOI: 10.1021/ja0111481] [Citation(s) in RCA: 314] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The combination of 1-benzenesulfinyl piperidine (BSP) and trifluoromethanesulfonic anhydride (Tf(2)O) forms a new, powerful, metal-free thiophile that can readily activate both armed and disarmed thioglycosides, via glycosyl triflates, in a matter of minutes at -60 degrees C in dichloromethane, in the presence of 2,4,6-tri-tert-butylpyrimidine (TTBP). The glycosyl triflates are rapidly and cleanly converted to glycosides, upon treatment with alcohols, in good yield and selectivity.
Collapse
Affiliation(s)
- D Crich
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL 60607-7061, USA
| | | |
Collapse
|
17
|
Martínez AG, Herrera A, Martínez R, Teso E, García A, Osío J, Pargada L, Unanue R, Subramanian LR, Hanack M. A new and convenient synthesis of alkyl and aryl pyrimidines. J Heterocycl Chem 1988. [DOI: 10.1002/jhet.5570250437] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
18
|
Engbersen JFJ, Koudijs A, Van Plas HCD. Homolytic alkylation of chromones in micellar solution. J Heterocycl Chem 1982. [DOI: 10.1002/jhet.5570190604] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
19
|
Dlugosz A, van der Plas HC, Van Veldhuizen A. On the reactivity ofN-benzylpyrimidinium salts with nitrogen nucleophiles. J Heterocycl Chem 1982. [DOI: 10.1002/jhet.5570190231] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|