151
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)01801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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152
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Abstract
We describe a single-step conversion of various N-vinyl and N-aryl amides to the corresponding pyrimidine and quinazoline derivatives, respectively. The process involves amide activation with 2-chloropyridine and trifluoromethanesulfonic anhydride followed by nitrile addition into the reactive intermediate and cycloisomerization. In situ nitrile generation from primary amides allows for their use as nitrile surrogates. The use of this chemistry with sensitive N-vinyl amides and epimerizable substrates in addition to a wide range of functional groups is noteworthy.
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Affiliation(s)
- Mohammad Movassaghi
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139, USA.
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153
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)00771-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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154
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Abstract
Palladium-catalyzed cross-coupling reactions of aryl perfluorooctanesulfonates with amines are introduced. Application of the fluorous tag in multistep synthesis of triaryl-substituted pyrimidine is also described.
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Affiliation(s)
- Wei Zhang
- Fluorous Technologies, Inc., University of Pittsburgh Applied Research Center 970 William Pitt Way, Pittsburgh, Pennsylvania 15238, USA
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155
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Movassaghi M, Hill MD. Synthesis of Substituted Pyridine Derivatives via the Ruthenium-Catalyzed Cycloisomerization of 3-Azadienynes. J Am Chem Soc 2006; 128:4592-3. [PMID: 16594694 DOI: 10.1021/ja060626a] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We describe a two-step conversion of various N-vinyl and N-aryl amides to the corresponding substituted pyridines and quinolines, respectively. The process involves the direct conversion of amides, including sensitive N-vinyl amides, to the corresponding trimethylsilyl alkynyl imines followed by a ruthenium-catalyzed protodesilylation and cycloisomerization. A wide range of new alkynyl imines are prepared and readily converted to the corresponding azaheterocycles.
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Affiliation(s)
- Mohammad Movassaghi
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139, USA.
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156
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Magnier E, Blazejewski JC, Tordeux M, Wakselman C. Straightforward One-Pot Synthesis of Trifluoromethyl Sulfonium Salts. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503776] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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157
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Magnier E, Blazejewski JC, Tordeux M, Wakselman C. Straightforward One-Pot Synthesis of Trifluoromethyl Sulfonium Salts. Angew Chem Int Ed Engl 2006; 45:1279-82. [PMID: 16416481 DOI: 10.1002/anie.200503776] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Emmanuel Magnier
- SIRCOB-CNRS, UMR 8086, Université de Versailles, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France.
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158
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Figueroa JS, Piro NA, Clough CR, Cummins CC. A Nitridoniobium(V) Reagent That Effects Acid Chloride to Organic Nitrile Conversion: Synthesis via Heterodinuclear (Nb/Mo) Dinitrogen Cleavage, Mechanistic Insights, and Recycling. J Am Chem Soc 2005; 128:940-50. [PMID: 16417385 DOI: 10.1021/ja056408j] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The transformation of acid chlorides (RC(O)Cl) to organic nitriles (RC[triple bond]N) by the terminal niobium nitride anion [N[triple bond]Nb(N[Np]Ar)3]- ([1a-N]-, where Np = neopentyl and Ar = 3,5-Me2C6H3) via isovalent N for O(Cl) metathetical exchange is presented. Nitrido anion [1a-N]- is obtained in a heterodinuclear N2 scission reaction employing the molybdenum trisamide system, Mo(N[R]Ar)3 (R = t-Bu, 2a; R = Np, 2b), as a reaction partner. Reductive scission of the heterodinuclear bridging N2 complexes, (Ar[R]N)3Mo-(mu-N2)Nb(N[Np]Ar)3 (R = t-Bu, 3b; R = Np, 3c) with sodium amalgam provides 1 equiv each of the salt Na[1a-N] and neutral N[triple bond]Mo(N[R]Ar)3 (R = t-Bu, 2a-N; R = Np, 2b-N). Separation of 2-N from Na[1a-N] is readily achieved. Treatment of salt Na[1a-N] with acid chloride substrates in tetrahydrofuran (THF) furnishes the corresponding organic nitriles concomitant with the formation of NaCl and the oxo niobium complex O[triple bond]Nb(N[Np]Ar)3 (1a-O). Utilization of 15N-labeled 15N2 gas in this chemistry affords a series of 15N-labeled organic nitriles establishing the utility of anion [1a-N]- as a reagent for the 15N-labeling of organic molecules. Synthetic and computational studies on model niobium systems provide evidence for the intermediacy of both a linear acylimido and niobacyclobutene species along the pathway to organic nitrile formation. High-yield recycling of oxo 1a-O to a niobium triflate complex appropriate for heterodinuclear N2 scission has been developed. Specifically, addition of triflic anhydride (Tf2O, where Tf = SO2CF3) to an Et2O solution of 1a-O provides the bistriflate complex, Nb(OTf)2(N[Np]Ar)3 (1a-(OTf)2), in near quantitative yield. One-electron reduction of 1a-(OTf)2 with either cobaltocene (Cp2Co) or Mg(THF)3(anthracene) provided the monotriflato complex, Nb(OTf)(N[Np]Ar)3 (1a-(OTf)), which efficiently regenerates complexes 3b and 3c when treated with the molybdenum dinitrogen anions [N2Mo(N[t-Bu]Ar)3]- ([2a-N2]-) or [N2Mo(N[Np]Ar)3]- ([2b-N2]-), respectively.
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Affiliation(s)
- Joshua S Figueroa
- Massachusetts Institute of Technology, Room 2-227, 77 Massachusetts Avenue, Cambridge Massachusetts 02139, USA
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159
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Shao L, Badger PD, Geib SJ, Cooper NJ. Vilsmeier−Haack−Arnold Acylation of the Reductively Activated Benzene Ligand in [Mn(CO)3(η4-C6H6)]-. Organometallics 2004. [DOI: 10.1021/om040103g] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Li Shao
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Paul D. Badger
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Steven J. Geib
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - N. John Cooper
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
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160
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Figueroa JS, Cummins CC. Phosphaalkynes from Acid Chlorides via P for O(Cl) Metathesis: A Recyclable Niobium Phosphide (P3-) Reagent that Effects C−P Triple-Bond Formation. J Am Chem Soc 2004; 126:13916-7. [PMID: 15506740 DOI: 10.1021/ja0461522] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reported herein is a new, metathetical P for O(Cl) exchange mediated by an anionic niobium phosphide complex that furnished phosphaalkynes (RCP) from acid chlorides (RC(O)Cl) under mild conditions. The niobaziridine hydride complex, Nb(H)(tBu(H)C=NAr)(N[Np]Ar)2 (1, Np = neopentyl, Ar = 3,5-Me2C6H3), has been shown previously to react with elemental phosphorus (P4), affording the mu-diphosphide complex, (mu2:eta2,eta2-P2)[Nb(N[Np]Ar)3]2, (2), which can be subsequently reduced by sodium amalgam to the anonic, terminal phosphide complex, [Na][PNb(N[Np]Ar)3] (3). It is now shown that treatment of 3 with either pivaloyl (t-BuC(O)Cl) or 1-adamantoyl (1-AdC(O)Cl) chloride provides the thermally unstable niobacyles, (t-BuC(O)P)Nb(N[Np]Ar)3 (4-t-Bu) and (1-AdC(O)P)Nb(N[Np]Ar)3 (4-1-Ad), which are intermediates along the pathway to ejection of the known phosphaalkynes t-BuCP (5-t-Bu) and 1-AdCP(5-1-Ad). Phosphaalkyne ejection from 4-t-Bu and 4-1-Ad proceeds with formation of the niobium(V) oxo complex ONb(N[Np]Ar)3 (6) as a stable byproduct. Preliminary kinetic measurements for fragmentation of 4-t-Bu to 5-t-Bu and 6 in C6D6 solution are consistent with a first-order process, yielding the thermodynamic parameters DeltaH = 24.9 +/- 1.4 kcal mol-1 and DeltaS = 2.4 +/- 4.3 cal mol-1 K-1 over the temperature range 308-338 K. Separation of volatile 5-t-Bu from 6 after thermolysis has been readily achieved by vacuum transfer in yields of 90%. Pure 6 is recovered after vacuum transfer and can be treated with 1.0 equiv of triflic anhydride (Tf2O, Tf = O2SCF3) to afford the bistriflate complex, Nb(OTf)2(N[Np]Ar)3 (7), in high yield. Complex 7 provides direct access to 1 upon reduction with magnesium anthracene, thus completing a cycle of element activation, small-molecule generation via metathetical P-atom transfer, and deoxygenative recycling of the final niobium(V) oxo product.
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Affiliation(s)
- Joshua S Figueroa
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
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161
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2004. [DOI: 10.1016/s0040-4020(04)01396-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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162
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Herrera A, Martı́nez-Álvarez R, Chioua R, Benabdelouahab F, Chioua M. Two simple and different approaches to the synthesis of new 2,4-dialkylamino substituted 6,7-dihydro-5H-benzocyclohepta[1,2-d]pyrimidines. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.04.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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163
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Zhang W, Chen CHT, Lu Y, Nagashima T. A highly efficient microwave-assisted suzuki coupling reaction of aryl perfluorooctylsulfonates with boronic acids. Org Lett 2004; 6:1473-6. [PMID: 15101770 PMCID: PMC1618883 DOI: 10.1021/ol0496428] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] A new strategy to improve the efficiency of Suzuki coupling reactions is introduced by combining fast microwave reaction with easy fluorous separation. Aryl perfluorooctylsulfonates derived from the corresponding phenols are coupled with aryl boronic acids to form biaryls under general microwave conditions. Both intermediates and products are purified by solid-phase extraction over FluoroFlash silica gel. Application of this tagging strategy to multistep synthesis of biaryl-substituted hydantoin is also described.
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Affiliation(s)
- Wei Zhang
- Fluorous Technologies, Inc., University of Pittsburgh Applied Research Center, 970 William Pitt Way, Pittsburgh, Pennsylvania 15238, USA.
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164
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Tetrahedron reports on organic chemistry. Tetrahedron 2004. [DOI: 10.1016/s0040-4020(04)00315-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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165
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The Literature of Heterocyclic Chemistry, Part VIII, 1999–2001. ADVANCES IN HETEROCYCLIC CHEMISTRY 2004. [DOI: 10.1016/s0065-2725(04)87001-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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166
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)01884-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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167
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)01130-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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168
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00841-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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169
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Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00323-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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170
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Posner G, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)01503-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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171
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On the regioselectivity in the reaction of aliphatic ketones and aromatic nitriles. Regiospecific synthesis of alkylarylpyrimidines. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)01300-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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172
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Laali KK, Borodkin GI. Exploratory study of the reaction of bis(2-methoxyethyl)aminosulfur trifluoride (Deoxofluor™ reagent) with diaryl sulfoxides: novel routes to Ar2SF2 and Ar2SF(OTf) via sulfoxide activation. J Fluor Chem 2002. [DOI: 10.1016/s0022-1139(02)00058-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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173
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Epperson MT, Gin DY. Enantiospecific Synthesis of the Bridged Pyrrolizidine Core of Asparagamine A: Dipolar Cycloadditions of Azomethine Ylides Derived from the Sulfonylation of Vinylogous Amides. Angew Chem Int Ed Engl 2002. [DOI: 10.1002/1521-3757(20020517)114:10<1856::aid-ange1856>3.0.co;2-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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174
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Herrera A, Martı́nez-Álvarez R, Ramiro P, Chioua M, Torres R. On the mechanism of reaction between ketones and nitriles. Unexpected results from benzyl nitriles. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00327-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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175
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Bengtson A, Hallberg A, Larhed M. Fast synthesis of aryl triflates with controlled microwave heating. Org Lett 2002; 4:1231-3. [PMID: 11922826 DOI: 10.1021/ol025701a] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Synthesis of aryl triflates from phenols using N-phenyltriflimide requires only 6 min for completion when conducted with controlled microwave heating. The methodology was applied to both solution- and solid-phase conditions. Ten different aryl triflates were synthesized and isolated in good yields. Applications in high-throughput chemistry are suggested.
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Affiliation(s)
- Anna Bengtson
- Department of Organic Pharmaceutical Chemistry, Uppsala University, BMC, Box-574, SE-751 23 Uppsala, Sweden
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176
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Pan Y, Ruhland B, Holmes CP. Use of a Perfluoroalkylsulfonyl (PFS) Linker in a “Traceless” Synthesis of Biaryls through Suzuki Cleavage. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20011203)113:23<4620::aid-ange4620>3.0.co;2-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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177
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Charette AB, Grenon M. Spectroscopic studies of the electrophilic activation of amides with triflic anhydride and pyridine. CAN J CHEM 2001. [DOI: 10.1139/v01-150] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The reaction of amides with trifluoromethanesulfonic (triflic) anhydride in the presence of pyridine was thoroughly investigated by NMR spectroscopic techniques. Different pyridinium intermediates were generated from secondary amides, tertiary amides with enolizable protons, and tertiary amides lacking enolizable protons. It was found that the actual triflating reagent is N-(trifluoromethylsulfonyl)pyridinium triflate 11 which is formed by the initial reaction of triflic anhydride with pyridine. The alcoholysis of these intermediates yields O-alkyliminium ethers which can then be easily hydrolyzed under mild acidic conditions to the corresponding esters.Key Words: amides, triflic anhydride, pyridinium intermediates, NMR study.
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