Penta‐2,4‐dien‐1‐ones by Formal [3+2] Cycloaddition–Rearrangement of Electron‐Deficient Diethyl 2‐(Dicyanomethylene)malonate with Alk­ynes

The reactions of diethyl 2-(dicyanomethylene)malonate, an electron-deficient alkene, with donor-activated and unactivated alkynes have been investigated. Moderately electron-rich and unactivated alkynes undergo efficient formal [3+2] cycloaddition–rearrangement cascades to provide the corresponding penta-2,4-dien-1-one adducts in yields of up to 84 %. The structures of the solid dienone products were confirmed by X-ray diffraction analysis. The buta-1,3-diene moieties in the dienones do not adopt planar s-trans conformations but rather nonplanar geometries in which the two olefinic bonds are nearly orthogonal to each other. This transformation proceeds with excellent regioselectivity and with a wide range of alkynes without the need for a catalyst. Under the optimized reaction conditions, no competition with the [2+2] cycloaddition–retroelectrocyclization reaction (CA–RE) was observed.

[1]  F. Diederich,et al.  Ester‐Substituted Electron‐Poor Alkenes for Cycloaddition–Retroelectrocyclization (CA–RE) and Related Reactions , 2015 .

[2]  F. Diederich,et al.  The [2 + 2] Cycloaddition-Retroelectrocyclization and [4 + 2] Hetero-Diels-Alder Reactions of 2-(Dicyanomethylene)indan-1,3-dione with Electron-Rich Alkynes: Influence of Lewis Acids on Reactivity. , 2015, Organic letters.

[3]  M. Kielmann,et al.  Reactions of Alkynyl‐ and 1,1′‐Dialkynylferrocenes with Tetracyanoethylene – Unanticipated Addition at the Less Electron‐Rich of Two Triple Bonds , 2015 .

[4]  F. Diederich,et al.  Strain-accelerated formation of chiral, optically active buta-1,3-dienes. , 2015, Angewandte Chemie.

[5]  C. Katan,et al.  High-yield formation of substituted tetracyanobutadienes from reaction of ynamides with tetracyanoethylene. , 2014, Chemistry.

[6]  B. Trost,et al.  An approach for rapid increase in molecular complexity: atom economic routes to fused polycyclic ring systems. , 2014, Organic letters.

[7]  F. Diederich,et al.  Post‐Cycloaddition–Retroelectrocyclization Transformations of Polycyanobutadienes , 2013 .

[8]  R. Hicklin,et al.  A ring-distortion strategy to construct stereochemically complex and structurally diverse compounds from natural products. , 2013, Nature chemistry.

[9]  E. Ortí,et al.  Tuning the electronic properties of nonplanar exTTF-based push-pull chromophores by aryl substitution. , 2012, The Journal of organic chemistry.

[10]  F. Diederich,et al.  6,6-Dicyanopentafulvenes: electronic structure and regioselectivity in [2 + 2] cycloaddition-retroelectrocyclization reactions. , 2012, Journal of the American Chemical Society.

[11]  T. Okujima,et al.  Synthesis of donor-acceptor chromophores by the [2 + 2] cycloaddition of arylethynyl-2H-cyclohepta[b]furan-2-ones with 7,7,8,8-tetracyanoquinodimethane. , 2012, Organic & biomolecular chemistry.

[12]  F. Diederich,et al.  N,N'-Dicyanoquinone diimide-derived donor-acceptor chromophores: conformational analysis and optoelectronic properties. , 2012, Organic letters.

[13]  Yongjun Li,et al.  Strong Charge‐Transfer Chromophores from [2+2] Cycloadditions of TCNE and TCNQ to Peripheral Donor‐Substituted Alkynes , 2011 .

[14]  G. Ulrich,et al.  Regioselective synthesis of 5-monostyryl and 2-tetracyanobutadiene BODIPY dyes. , 2011, Organic letters.

[15]  T. Michinobu,et al.  Photochemical control of a highly efficient addition reaction between electron-rich alkynes and tetracyanoethylene. , 2011, Chemical communications.

[16]  Philippe Blanchard,et al.  Triphenylamine/tetracyanobutadiene-based D-A-D π-conjugated systems as molecular donors for organic solar cells. , 2011, Organic letters.

[17]  M. Bruce.  Some Organometallic Chemistry of Tetracyanoethene: CN-displacement and Cycloaddition Reactions with Alkynyl–Transition Metal Complexes and Related Chemistry , 2011 .

[18]  F. Diederich,et al.  Non-planar push-pull chromophores. , 2010, Chemical communications.

[19]  F. Diederich,et al.  Mechanistic investigation of the dipolar [2+2] cycloaddition-cycloreversion reaction between 4-(N,N-dimethylamino)phenylacetylene and arylated 1,1-dicyanovinyl derivatives to form intramolecular charge-transfer chromophores. , 2010, Chemistry.

[20]  F. Diederich,et al.  New donor-acceptor chromophores by formal [2+2] cycloaddition of donor-substituted alkynes to dicyanovinyl derivatives. , 2009, Organic & biomolecular chemistry.

[21]  F. Diederich,et al.  A novel reaction of 7,7,8,8-tetracyanoquinodimethane (TCNQ): charge-transfer chromophores by [2 + 2] cycloaddition with alkynes. , 2007, Chemical communications.

[22]  F. Diederich,et al.  Donor-substituted 1,1,4,4-tetracyanobutadienes (TCBDS): new chromophores with efficient intramolecular charge-transfer interactions by atom-economic synthesis. , 2006, Chemistry.

[23]  Ivan Biaggio,et al.  A new class of organic donor-acceptor molecules with large third-order optical nonlinearities. , 2005, Chemical communications.

[24]  R. Hsung,et al.  A copper-catalyzed C-N bond formation involving sp-hybridized carbons. A direct entry to chiral ynamides via N-alkynylation of amides. , 2003, Journal of the American Chemical Society.

[25]  Luke G Green,et al.  A stepwise huisgen cycloaddition process: copper(I)-catalyzed regioselective "ligation" of azides and terminal alkynes. , 2002, Angewandte Chemie.

[26]  A. Padwa,et al.  Synthetic applications of 1,3-dipolar cycloaddition chemistry toward heterocycles and natural products , 2002 .

[27]  Morten Meldal,et al.  Peptidotriazoles on solid phase: [1,2,3]-triazoles by regiospecific copper(i)-catalyzed 1,3-dipolar cycloadditions of terminal alkynes to azides. , 2002, The Journal of organic chemistry.

[28]  M. Lautens,et al.  Transition Metal-Mediated Cycloaddition Reactions. , 1996, Chemical reviews.

[29]  Barry M. Trost,et al.  Atom Economy—A Challenge for Organic Synthesis: Homogeneous Catalysis Leads the Way , 1995 .

[30]  P. J. Toscano,et al.  Total Synthesis of Thiarubrine B [3-(3-Buten-1-ynyl)-6-(1,3-pentadiynyl)-1,2-dithiin], the Antibiotic Principle of Giant Ragweed (Ambrosia trifida) , 1994 .

[31]  B. Trost,et al.  The atom economy--a search for synthetic efficiency. , 1991, Science.

[32]  T. Hudlický,et al.  Anionic approaches to the construction of cyclopentanoids , 1989 .

[33]  F. Klärner,et al.  1,5‐EIectrocyclization in Homofuran, Homopyrrole, and Homothiophene , 1987 .

[34]  R. Criegee.  Mechanism of Ozonolysis , 1975 .

[35]  Günter Szeimies,et al.  1.3-Dipolare Cycloadditionen, XXXII. Kinetik der Additionen organischer Azide an CC-Mehrfachbindungen , 1967 .

[36]  R. Huisgen,et al.  Stereospecific Conversion of cis-trans Isomeric Aziridines to Open-Chain Azomethine Ylides , 1967 .

[37]  R. Huisgen.  1,3-Dipolar Cycloadditions. Past and Future† , 1963 .

[38]  G. D'alcontres,et al.  A New Reaction of Ethylenic Double Bonds , 1950, Nature.

[39]  P. Schiess,et al.  Valenzisomerisierung von cis‐Dienonen I. 2‐Vinyl‐3,4,5,6‐tetrahydrobenzaldehyd; Pyrolyse. von 6‐Oxabicyclo [3,1,0] hex‐2‐en [1] , 1970 .

[40]  R. Huisgen,et al.  1.3-Cycloadditionen von azomethin-yliden aus aziridin-carbonestern , 1966 .