[5C + 1N] annulations: two novel routes to substituted dihydrofuro[3,2-c]pyridines.

Two novel routes based on [5C + 1N] annulations for the synthesis of 2,3-dihydrofuro[3,2-c]pyridines are described. Ammonium acetate (NH(4)OAc) is used as an ammonia source in both routes. The first route utilizes 1-acyl-1-[(dimethylamino)alkenoyl]cyclopropanes as a five-carbon 1,5-bielectrophilic species and combines the [5C + 1N] annulation and regioselective ring-enlargement of cyclopropyl ketone into one pot, whereas the second route utilizes 3-acyl-2-[(dimethylamino)alkenyl]-4,5-dihydrofurans as the five-carbon synthons, which involves a sequential intermolecular aza-addition, intramolecular aza-nucleophilic addition/elimination, and dehydration reaction.

[1]  Uroš Grošelj,et al.  A simple metal-free synthesis of 2-substituted pyridine-4,5-dicarboxylates and their N -oxides , 2012 .

[2]  Yongjiu Liang,et al.  Formal [4+1] Annulation of Cyclopropyl Amides and Water Mediated by Lewis Acid: A Novel Entry to γ-Butyrolactones , 2012 .

[3]  Fu‐She Han,et al.  Synthesis of densely substituted α,β,γ,δ-dienones via the Pd(II)-catalyzed allylation, H-migration, and aerobic oxidative δ-hydride elimination cascade. , 2012, Organic letters.

[4]  Peng-mian Huang,et al.  Lawesson's reagent-initiated domino reaction of aminopropenoyl cyclopropanes: synthesis of thieno[3,2-c]pyridinones. , 2012, Organic & biomolecular chemistry.

[5]  F. Liang,et al.  Halonium-initiated C-O bond formation via umpolung of α-carbon to the carbonyl: efficient access to 5-amino-3(2H)-furanones. , 2012, Organic letters.

[6]  Peng-mian Huang,et al.  Vilsmeier-type reaction of dimethylaminoalkenoyl cyclopropanes: one-pot access to 2,3-dihydrofuro [3,2-c]pyridin-4(5H)-ones. , 2012, Organic letters.

[7]  Q. Fu,et al.  Halonium-initiated electrophilic cascades of 1-alkenoylcyclopropane carboxamides: efficient access to dihydrofuropyridinones and 3(2H)-furanones. , 2011, Chemical communications.

[8]  Xiaolan Fu,et al.  Divergent synthesis of fully substituted isoxazoles and spiro-fused pyrazolin-5-ones from cyclopropyl oximes , 2011 .

[9]  M. Shaaban,et al.  Construction of Fused Heterocycles by Metal-mediated [2+2?+?2] Cyclotrimerization of Alkynes And/or Nitriles , 2011 .

[10]  Masaharu Nakayama,et al.  Synthesis of a novel series of tricyclic dihydrofuran derivatives: discovery of 8,9-dihydrofuro[3,2-c]pyrazolo[1,5-a]pyridines as melatonin receptor (MT1/MT2) ligands. , 2011, Journal of medicinal chemistry.

[11]  H. Maruoka,et al.  A convenient approach to the synthesis of furo- and thieno-〔3,2-c〕pyridine derivatives , 2010 .

[12]  P. Langer,et al.  Domino [3+3] Annulation/Ring‐Cleavage Reactions of 1,3‐Bis(trimethylsilyloxy)‐1,3‐butadienes with 5‐Aryl‐ and 5‐Vinyl‐3‐acyl‐ 4,5‐dihydrofurans: Efficient Synthesis of 5‐(4‐Chlorobut‐2‐en‐1‐yl)‐ and 5‐(2‐Aryl‐2‐chloroethyl)salicylates , 2010 .

[13]  S. C. Mojumdar,et al.  Thermal properties of solid complexes with biologically important heterocyclic ligands , 2010 .

[14]  M. Kerr,et al.  Heterocycles from cyclopropanes: applications in natural product synthesis. , 2009, Chemical Society reviews.

[15]  Yongjiu Liang,et al.  N,N,N′,N′-Tetramethylchloroformamidinium Chloride-Mediated Cyclizations of β-Oxo Amides: Facile and Divergent One-Pot Synthesis of Substituted 2H-Pyrans, 4H-Pyrans and Pyridin-2(1H)-ones , 2009 .

[16]  R. Rickert,et al.  Improved synthesis of 3-substituted-4-amino-[3,2-c]-thienopyridines. , 2009, The Journal of organic chemistry.

[17]  Xiaolan Fu,et al.  PIFA-mediated oxidative cyclization of 1-carbamoyl-1-oximylcycloalkanes: synthesis of spiro-fused pyrazolin-5-one N-oxides. , 2009, Organic letters.

[18]  Xin Cheng,et al.  A new route to multifunctionalized p-terphenyls and heteroaryl analogues via [5C + 1C(N)] annulation strategy. , 2009, The Journal of organic chemistry.

[19]  J. Moncol’,et al.  Synthesis, spectroscopic properties, crystal structure and biological activities of copper(II) 2-methylthionicotinate complexes with furopyridines , 2009 .

[20]  D. Agrawal,et al.  Silylmethyl-substituted cyclopropyl and other strained ring systems: cycloaddition with dipolarophiles. , 2008, Chemical communications.

[21]  P. Langer,et al.  Synthesis of 5-(2-aryl-2-haloethyl)salicylates by the first domino ‘[3+3] cyclization/ring-cleavage’ reactions of 1,3-bis(silyloxy)-1,3-butadienes with 3-acetyl-5-aryl-4,5-dihydrofurans , 2008 .

[22]  Yongjiu Liang,et al.  Ring-enlargement of dimethylaminopropenoyl cyclopropanes: an efficient route to substituted 2,3-dihydrofurans. , 2008, The Journal of organic chemistry.

[23]  H. Reissig,et al.  Novel Furo-pyridine Derivatives via Sonogashira Reactions of Functionalized Pyridines , 2008 .

[24]  L. Kiss,et al.  Efficient synthesis of 2-(trifluoromethyl)nicotinic acid derivatives from simple fluorinated precursors. , 2008, Organic letters.

[25]  D. Dong,et al.  Efficient and divergent synthesis of fully substituted 1H-pyrazoles and isoxazoles from cyclopropyl oximes. , 2008, Organic letters.

[26]  Jae Nyoung Kim,et al.  Regioselective synthesis of 1,2,4,5-tetrasubstituted pyridines from Baylis–Hillman adducts via consecutive [3+2+1] annulation protocol , 2008 .

[27]  Q. Zhang,et al.  Temperature-controlled synthesis of substituted pyridine derivatives via the [5C + 1N] annulation of 1,1-bisalkylthio-1,4-pentanedienes and ammonium acetate. , 2008, The Journal of organic chemistry.

[28]  Liming Zhang,et al.  Au-containing all-carbon 1,4-dipoles: generation and [4 + 2] annulation in the formation of carbo-/heterocycles. , 2008, Journal of the American Chemical Society.

[29]  Qun Liu,et al.  Efficient one-pot synthesis of highly substituted pyridin-2(1H)-ones via the Vilsmeier-Haack reaction of 1-acetyl,1-carbamoyl cyclopropanes. , 2007, Organic letters.

[30]  J. D. Stuart,et al.  Design and effective synthesis of novel templates, 3,7-diphenyl-4-amino-thieno and furo-[3,2-c]pyridines as protein kinase inhibitors and in vitro evaluation targeting angiogenetic kinases. , 2007, Bioorganic & medicinal chemistry letters.

[31]  Q. Zhang,et al.  Domino ring-opening/recyclization reactions of doubly activated cyclopropanes as a strategy for the synthesis of furoquinoline derivatives. , 2007, Angewandte Chemie.

[32]  William L Jorgensen,et al.  FEP-guided selection of bicyclic heterocycles in lead optimization for non-nucleoside inhibitors of HIV-1 reverse transcriptase. , 2006, Journal of the American Chemical Society.

[33]  Junliang Zhang,et al.  Gold(I)-catalyzed reaction of 1-(1-alkynyl)-cyclopropyl ketones with nucleophiles: a modular entry to highly substituted furans. , 2006, Angewandte Chemie.

[34]  M. Kerr,et al.  Synthesis and cross-coupling reactions of 7-azaindoles via a new donor-acceptor cyclopropane. , 2006, Organic letters.

[35]  Jeffrey S. Johnson,et al.  Nickel-catalyzed rearrangement of 1-acyl-2-vinylcyclopropanes. A mild synthesis of substituted dihydrofurans. , 2006, Organic letters.

[36]  Qian Zhang,et al.  [5C + 1S] annulation: a facile and efficient synthetic route toward functionalized 2,3-dihydrothiopyran-4-ones. , 2005, The Journal of organic chemistry.

[37]  R. Boča,et al.  Structural characterization, spectral and magnetic properties of isothiocyanate nickel(II) complexes with furopyridine derivatives , 2005 .

[38]  Qun Liu,et al.  [5C + 1N] annulation: a novel synthetic strategy for functionalized 2,3-dihydro-4-pyridones. , 2005, Chemical communications.

[39]  S. C. Mojumdar,et al.  Furopyridines and furopyridine-Ni(II) complexes , 2005 .

[40]  S. Ōmura,et al.  Citridones, New Potentiators of Antifungal Miconazole Activity, Produced by Penicillium sp. FKI-1938 , 2005, The Journal of Antibiotics.

[41]  D. Craig,et al.  Sulfone-mediated synthesis of polysubstituted pyridines , 2005 .

[42]  Bing Li,et al.  [5 + 1] annulation: a synthetic strategy for highly substituted phenols and cyclohexenones. , 2005, Journal of the American Chemical Society.

[43]  Ming‐Shiuan Yu,et al.  Recent advances in donor-acceptor (DA) cyclopropanes , 2005 .

[44]  Zhaohua Yan,et al.  Synthesis of 2,3-Dihydrofuro[3,2-c]pyridine-3,4-dicarboxylic Acid, a Conformationally Constrained Analogue of the Subtype Selective NMDA Receptor Agonist Homoquinolinic Acid , 2004 .

[45]  G. Henry.  De novo Synthesis of Substituted Pyridines , 2004 .

[46]  Jesús A. Varela,et al.  Construction of pyridine rings by metal-mediated [2 + 2 + 2] cycloaddition. , 2003, Chemical reviews.

[47]  R. Zimmer,et al.  Donor-acceptor-substituted cyclopropane derivatives and their application in organic synthesis. , 2003, Chemical reviews.

[48]  G. Fabrizi,et al.  Electrophilic cyclization of o-acetoxy- and o-benzyloxyalkynylpyridines: an easy entry into 2,3-disubstituted furopyridines. , 2002, Organic letters.

[49]  Y. Sugie,et al.  CJ-15,696 and its analogs, new furopyridine antibiotics from the fungus Cladobotryum varium: fermentation, isolation, structural elucidation, biotransformation and antibacterial activities. , 2002, The Journal of antibiotics.

[50]  I. Davies,et al.  A general preparation of pyridines and pyridones via the annulation of ketones and esters. , 2001, The Journal of organic chemistry.

[51]  D. N. Bobrov,et al.  Synthesis of 5-alkyl-4-amino-2-(trifluoromethyl)pyridines and their transformation into trifluoromethylated 1H-pyrazolo[4,3-c]pyridines , 2001 .

[52]  T. Kitamura,et al.  Novel heteroaromatic CH insertion of alkylidenecarbenes. A new entry to furopyridine synthesis , 1998 .

[53]  S. Shiotani.  Furopyridines. Synthesis and Properties , 2010 .

[54]  A. de Meijere,et al.  Thermal Rearrangement of Nitrone and Nitrile Oxide Cycloadducts to Bicyclopropylidene.(1) Synthesis of 3-Spirocyclopropane-4-pyridone and Furo[2,3-c]pyridine Derivatives. , 1996, The Journal of organic chemistry.

[55]  D. Powell,et al.  New Synthetic Routes to 3-, 5-, and 6-Aryl-2-chloropyridines , 1995 .

[56]  D. Scopes,et al.  4-[(Alkylamino)methyl]furo[3,2-c]pyridines: a new series of selective kappa-receptor agonists. , 1994, Journal of medicinal chemistry.

[57]  R. Ruzziconi,et al.  Electronic and steric effects in the addition of electrophilic 1,3-dicarbonylalkyl radicals to styrenes , 1991 .

[58]  L. Alekseeva,et al.  Acetals of lactam and amide acids. 59. Synthesis of derivatives of bis(benzofuryl-3)ketones , 1990 .

[59]  P. Molina,et al.  An efficient iminophosphorane-mediated synthesis of thieno[3,2-c]pyridine, thieno[2,3-c]pyridine and furo[3,2-c]-pyridine derivatives , 1987 .

[60]  R. Abramovitch,et al.  Consecutive 3,5 shifts in pyridine 1-oxide rearrangements. One-step furopyridine synthesis , 1975 .

[61]  F. Eloy,et al.  Sur la synthèse des furo[3,2-c] pyridines , 1971 .

[62]  W. Herz,et al.  Furano(3,2-c)pyridines1 , 1955 .