Structural elucidation of homometallic anthracenolates synthesised via deprotonative metallation of anthrone.

Five novel neutral homometallic complexes which contain the anthracen-9-olate anion have been prepared and characterised by treating anthrone with an organometallic base to induce aromatisation. Three of these complexes [(donor)·M(OC(14)H(9))](2) (2-4) are dimeric and contain sodium, lithium and potassium respectively. For 2 and 3 the donor is N,N,N',N'-tetramethylethylenediamine (TMEDA) whilst for 4 it is N,N,N',N'',N''-pentamethyldiethylenetriamine (PMDETA). When bimetallic reagents such as [(TMEDA)·Na(μ-(t)Bu)(μ-TMP)Zn((t)Bu)] are employed, only the alkali-metal-containing species is isolated (e.g., 2 in this case). Providing a contrast, complexes 5 [(TMEDA)·Mg(OC(14)H(9))(n)Bu] and 6 [(TMEDA)·Zn(OC(14)H(9))Et] are monomeric. The alkali metal complexes were prepared by reacting anthrone with one molar equivalent of either n-butylsodium, n-butyllithium or (trimethylsilyl)methylpotassium in the presence of the required donor solvent. For 5 and 6, equimolar quantities of di-n-butylmagnesium and diethylzinc, respectively, were reacted with anthrone in the presence of TMEDA. The solid-state structures and the arene solution structures of 2-6 have been determined by X-ray crystallography and NMR spectroscopy respectively.

[1]  J. Klett,et al.  Remote functionalisation via sodium alkylamidozincate intermediates: access to unusual fluorenone and pyridyl ketone reactivity patterns. , 2011, Chemical communications.

[2]  D. Armstrong,et al.  Structural Basis for Regioisomerization in the Alkali-Metal-Mediated Zincation (AMMZn) of Trifluoromethyl Benzene by Isolation of Kinetic and Thermodynamic Intermediates , 2010, Journal of the American Chemical Society.

[3]  K. Ehrlich,et al.  HypC, the Anthrone Oxidase Involved in Aflatoxin Biosynthesis , 2010, Applied and Environmental Microbiology.

[4]  Jason W. Labonte,et al.  Structure and function of an iterative polyketide synthase thioesterase domain catalyzing Claisen cyclization in aflatoxin biosynthesis , 2010, Proceedings of the National Academy of Sciences.

[5]  J. Klett,et al.  Structural elaboration of the surprising ortho-zincation of benzyl methyl ether. , 2010, Chemical communications.

[6]  R. Arumugham,et al.  Automation of the anthrone assay for carbohydrate concentration determinations. , 2010, Analytical Chemistry.

[7]  J. Klett,et al.  Potassium-mediated zincation of ferrocene and ruthenocene: potassium, the architect behind supramolecular structural variations. , 2010, Dalton transactions.

[8]  Jason W. Labonte,et al.  Structural basis for biosynthetic programming of fungal aromatic polyketide cyclization , 2009, Nature.

[9]  D. Armstrong,et al.  Synthetic and structural insights into the zincation of toluene: direct synergic ring metallation versus indirect nonsynergic lateral metallation. , 2009, Chemistry.

[10]  R. Mulvey.  Avant-garde metalating agents: structural basis of alkali-metal-mediated metalation. , 2009, Accounts of chemical research.

[11]  Guang Li,et al.  Synthesis and properties of fluorinated poly(ether ketone imide)s based on a new unsymmetrical and concoplanar diamine : 3,5-Dimethyl-4-(4-amino-2-trifluoromethylphenoxy)-4'-aminobenzophenone , 2009 .

[12]  D. Armstrong,et al.  Metalation of 2,4,6-Trimethylacetophenone Using Organozinc Reagents: The Role of the Base in Determining Composition and Structure of the Developing Enolate , 2008 .

[13]  J. Klett,et al.  Structurally-defined potassium-mediated regioselective zincation of amino- and alkoxy-substituted pyridines. , 2008, Chemical communications.

[14]  Keisuke Suzuki,et al.  Total synthesis and structure assignment of the anthrone C-glycoside cassialoin. , 2008, Angewandte Chemie.

[15]  A. Kennedy,et al.  Structurally-defined direct C-magnesiation and C-zincation of N-heterocyclic aromatic compounds using alkali-metal-mediated metallation. , 2007, Chemical communications.

[16]  Y. Kondo,et al.  Deprotonative metalation using ate compounds: synergy, synthesis, and structure building. , 2007, Angewandte Chemie.

[17]  D. Armstrong,et al.  Dizincation and dimagnesiation of benzene using alkali-metal-mediated metallation. , 2007, Chemical communications.

[18]  W. Clegg,et al.  Alkali-metal-mediated zincation of polycyclic aromatic hydrocarbons: synthesis and structures of mono- and dizincated naphthalenes. , 2006, Angewandte Chemie.

[19]  D. Armstrong,et al.  Directed meta-metalation using alkali-metal-mediated zincation. , 2006, Angewandte Chemie.

[20]  M. Hlavinka,et al.  The direct α-zincation of amides, phosphonates and phosphine oxides by H–Zn exchange , 2005 .

[21]  W. Clegg,et al.  Alkali-metal-mediated zincation of ferrocene: synthesis, structure, and reactivity of a lithium tmp/zincate reagent. , 2005, Angewandte Chemie.

[22]  A. Kennedy,et al.  Trapping, stabilization, and characterization of an enolate anion of a 1,6-adduct of benzophenone chelated by a sodium alkylamidozincate cation. , 2005, Journal of the American Chemical Society.

[23]  A. Kennedy,et al.  Isolation and characterisation of the mixed-metal alkyl amide [(TMEDA)Na(mu-Bu)(mu-TMP)Mg(TMP)], an unexpected chelate-trapped intermediate in the formation of inverse crowns. , 2004, Chemical communications.

[24]  G. Cordell,et al.  Anthrone and oxanthrone C-glycosides from Picramnia latifolia collected in Peru. , 2004, Journal of natural products.

[25]  V. Cherkasov,et al.  Reduction of benzophenone and 9(10H)-anthracenone with the magnesium complex [(2,6-iPr2C6H3-bian)Mg(thf)3]. , 2003, Chemistry.

[26]  H. G. Richey,et al.  Hammett ρ of reactions of MeLi with benzophenones , 2002 .

[27]  Leonard J. Barbour,et al.  Supramolecular Chemistry And Self-assembly Special Feature: Probing alkali metal–π interactions with the side chainresidue of tryptophan , 2002 .

[28]  Claire McDonnell,et al.  Enol–keto tautomerism of 9-anthrol and hydrolysis of its methyl ether , 2002 .

[29]  Jonathan G Maclellan,et al.  Landmark Crystal Structure of an Experimentally Utilized Tetralithium-Tetrapotassium Amide-Alkoxide Superbase. , 2001, Angewandte Chemie.

[30]  R. Mulvey.  s-Block metal inverse crowns: synthetic and structural synergism in mixed alkali metal–magnesium (or zinc) amide chemistry , 2001 .

[31]  G. Gokel,et al.  Alkali metal cation-pi interactions observed by using a lariat ether model system. , 2001, Journal of the American Chemical Society.

[32]  C. Raston,et al.  An Unprecedented Hexapotassium-Hexamagnesium 24-Membered Macrocyclic Amide: A Polymetallic Cationic Host to Six Monodeprotonated Arene Anions , 2000 .

[33]  D. Armstrong,et al.  Mixed-metal sodium-magnesium macrocyclic amide chemistry: A template reaction for the site selective dideprotonation of arene molecules , 1999 .

[34]  P. Schleyer,et al.  n-Butylsodium: The preparation, properties and NMR spectra of a hydrocarbon- and tetrahydrofuran-soluble reagent , 1985 .

[35]  Jerry March,et al.  Advanced Organic Chemistry: Reactions, Mechanisms, and Structure , 1977 .

[36]  S. N. Srivastava.  Three-dimensional refinement of the structure of anthrone , 1964 .

[37]  D. Jiang,et al.  Study on Compatibilization of Polyethersulfone/poly (Aryl ether ketone) containing 1,4-Naphthalene blends , 2010 .

[38]  G. Sheldrick.  A short history of SHELX. , 2008, Acta crystallographica. Section A, Foundations of crystallography.

[39]  Wesley L. Archer,et al.  Industrial solvents handbook , 1996 .