Siderophore, II. Tetrazolylenolat‐ und Semicorrinat‐Anionen als Chelatliganden für Eisen(II)‐und Kupfer(II)‐Ionen: Vom Molekül zum Kollektiv. Siderophores, II<sup>[1]</sup>. – Tetrazolyl Enolate and Semicorrinate Anions as Chelate Ligands for Iron(II) and Copper(II) Ion: From Molecular to Collective Structures

Saalfrank, Rolf W.; Struck, Oliver; Nunn, Kurt; Lurz, Claus‐Jürgen; Harbig, Roland; Peters, Karl; Schnering, Hans Georg̀ von; Bill, Eckhard; Trautweinc, Alfred X.

doi:10.1002/cber.19921251022

Cited by 28 publications

(8 citation statements)

References 21 publications

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“…In this section we demonstrate that compounds similar to 20, like 109-115 (HL 1-7 ), 74 allow the construction of various coordination polymers. [75][76][77][78][79][80][81][82][83][84][85][86][87][88] In principle, the monoanionic bidentate ligands (L 1-7 ) 2 give rise to the neutral, coordinatively-unsaturated building blocks 116-122 with two extra CN-donor groups. Thus, the monomers 116-122 are self complementary and consist of both coordinatively-unsaturated metals and bidentate CN-ligands that yield various 1D-, 2D-and 3D-coordination polymers 101-108 (Scheme 29, Fig.…”

Section: One- Two-and Three-dimensional Coordination Polymersmentioning

confidence: 99%

Roots: From carbenes to allenes and coordination polymers : Ever present never twice the same

Saalfrank

Maid

2005

Chem. Commun.

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The purpose of this Feature Article is to demonstrate that recognizing the similarities in different areas of chemistry allows the prediction of potential results in related fields. For instance, during our investigations of 2,2-diethoxyvinylidene-triphenylphosphorane we became interested in 2,2-diethoxydiazoethene. In order to obtain diazoethenes, we studied vinyl-diazonium salts and geminal vinyl-diazides as precursors. In the course of these investigations, we realized their synthetic potential to produce, via substituent-dependent 1,5-, 3,5-, or 1,5'-cyclization, a whole variety of heterocycles. However, more importantly, we became familiar with the chemistry of carbenes, which prompted an investigation of the carbene-like character of push-pull substituted allenes. Due to the ambiphilicity of their central carbon atom, they readily dimerized. Consequently, our strong interests in push-pull substituted allenes drew our attention to tetradonor substituted allenes, and as a result, we employed tetraethoxyallene as a synthetic equivalent to the fictitious malonic ester 1,1-/1,3-dianion synthon. This concept led to the synthesis of heterocumulenes and to the transallenation reaction to give allenecarboxanilides, which was further developed as a cumuhomologation for the synthesis of butatrienes via haloallenes from propargyl alcohols. The Diels-Alder reaction and intramolecular domino cyclization of multi-functional allenecarboxanilides yielded complex fused heteroarenes. Finally, the 1,5-cyclization of vinyl-azides, reported earlier, provided tetrazolylidene ligands, triggering our interest in supramolecular coordination chemistry, for example, the synthesis of one-, two- and three-dimensional coordination polymers.

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Section: One- Two-and Three-dimensional Coordination Polymersmentioning

confidence: 99%

Roots: From carbenes to allenes and coordination polymers : Ever present never twice the same

Saalfrank

Maid

2005

Chem. Commun.

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“…Cu---N(IOB) 257, 196 , (4) 145,1(6) C(2)-C(l 1) 154,1(7) C(4)-N (5) 136,6(5) C(3)-C(9) 141,2(7) N(5)-N (6) 136,8 (6) C(4)-N(8) 133,3(6) N(6)-N (7) 127,2(5) N(5)-C ( 15) 150,3(6) C(9)-N (10) 114,6(7) N(7)-N(8) 136,4(5) C (11)-C ( 13) 152,1 (7) C (11 )-C (12) 153,9(9) C(15)-C (16) 152,7 (7) C (11)-C ( 14) 154,0(8) C(15)-C (18) 151,4 (7) C (15) (4) 604 (3) 30(1) C (4) 1592 (3) -1775 (4) 1609 (4) 29(1) N (5) 2015 (3) -1934 (3) 2817 (3) 33(1) N (6) 1661 (3) -905 (4) 3388 (3) 42(1) N (7) 1050 (3) -185 (4) 2592 (3) 40(1) N (8) 991 (3) -685 (4) 1474 (3) 32(1) C (9) 2657(4) -3366 (5) 713 (4) 40(2) N ( 10) 3414 (4) -4011 (5) 768 (4) 61(2) C (11) 1003 (4) -3342(5) -1605 (4) 43(2) C (12) 2029 (5) -2959 …”

Section: Tab I Ausgewählte Bindungslängen [Pm] Vonunclassified

Verknüpfung koordinativ ungesättigter Kupfer(II)-Monomere via Cyano-versus Tetrazolyl-Donor/ Linkage of Coordinatively Unsaturated Copper(II) Monomers via Cyano versus Tetrazolyl Donor

Saalfrank

Harbig

Struck

et al. 1996

Zeitschrift Für Naturforschung B

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Reaction of a methanolic copper(II) acetate solution with tetrazolyl enol derivatives 2a (HL2) or 2b (HL3) leads to the formation of the corresponding 2D-coordination polymers 4 (^ [CuL^]) and 5 (^ [CuL2]), respectively. Single-crystal X-ray diffraction of the supramolecular species 4 and 5 established unequivocally the structures of the regioisomeric coordination polymers. On the contrary, reactions of 2c (HL4) with methanolic copper(II) acetate solution and 2b (HL3) with methanolic zinc(II) acetate solution yield mononuclear chelate complexes 11 ([CuL2]) and 12 ([ZnL2(MeOH)2]). The structures of 11 and 12 have been established by X-ray structure analysis. Einleitung A uf dem G ebiet der S upram olekularen C hem ie sind polym ere Ü bergangsm etallkom plexe als bio anorganische M odellsystem e [2], wie auch auf grund ihrer M aterialeigenschaften (Leitfähigkeit, M agnetism us) [3, 4], G egenstand zahlreicher U n tersuchungen. Besondere B edeutung kom m t dabei zw eidim ensionalen (2D ) System en m it kooperati ven Effekten zu. Ein E tappenziel au f dem Weg zu funktionellen supram olekularen M aterialien und N etzw erken ist die K onstruktion von pro g ra m m ier ten selbstorganisierenden System en [5]. Im Rahm en unserer Forschungsarbeiten berich teten w ir über die Synthese und röntgenographische C harakterisierung des neutralen 2D -K oordinationspolym eren3 [6] der allgem einen Zusam m ensetzung ^ [CuL^] [7] (H L 1 = 1, C u V 2 = 6), das ausge hend von K upfer(II)-acetat und dem verbrücken den Pyrrolidin-L iganden 1 [8] bequem zugänglich ist. Die Verknüpfung der aufgrund der beiden CN-Gruppen zw eizähnigen M onom ere 6 untereinander * Sonderdruckanforderungen an Prof. Dr. R. W. Saalfrank. sättigt die C u(II)-Zentren koordinativ ab, wobei sich das entsprechende K oordinationspolym er 3 bil det. Die koordinativ ungesättigten Interm ediate 6 CN R2 Cu(OAc)2 1,2 1 (HL1): X, Y, Z = CH2; R2 = OMe 2a (HL2): X = NR1; Y -Z = HT=N; R1 = CMe3; R2 = CMe3 2b (HL3): X = NR1; Y -Z = N2= N ; R1 = Ph; R2 = Me 2c (HL4): X = NR1; Y -Z = N2= N ; R1 = Ph; R2 = OMe 2d (HL5): X = NR1; Y -Z = N*=N; R1 = CMe3; R2 = OMe 4: (i[C u L 22]) 5: ( J [C uL32]) 11: ([CuL 2])0 9 3 9 -5 0 7 5 /9 6 /0 3 0 0 -0 3 9 9 $ 06.00

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“…4-(Cyanomethylene)-2,2,5,5-tetramethylimidazolidinel-oxyl (8). A mixture of chloro derivative 7a (0.3 g, 1 retool) and NaCN (0.1 g, 2 retool) in methanol (10 mL) was refluxed for 20 rain and then concentrated.…”

Section: -(2~carbamoyl-l-ddoro-2-oxoetbylidenel-z;-2-55-tetramethymentioning

confidence: 99%

“…cyano-substituted enaminoketonates can form crystal structures favorable for magnetic phase transitions. 8,9 In this connection, the aim of this work was to study the reactions of chloro-substituted enaminoketones 7 with NaCN.…”

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confidence: 99%

Reactions of chloro-substituted enaminoketones,viz., derivatives of imidazolidine nitroxides, with sodium cyanide

2000

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The reactions of chtoro-substituted enaminoketones, viz., derivatives of imidazolidine nitroxides, with sodium cyanide afford the corresponding nitriles. The reactions proceed through formation of epoxides. The structure of one of these epoxides was confirmed by X-ray diffraction analysis.Key words: nitroxides, enaminoketones, imidazolidines, epo• nucteophilic substitution.Enaminoketones are vinylogs of amides, and their carbonyl groups exhibit reduced reactivity with respect to nucleophilic addition, j Derivatives of imidazolidine nitroxides 1 are no exception.Thus. compounds 1 were prepared by the reactions of imidazolidine 2 with esters in the presence of lithium diisopropylamide (LDA)_ z-4 In no case was the formation of compounds 3, which are products of the addition of two molecules 2 to the ester molecule, observed whatever the order in which the reagents were mixed and their ratio. Enaminoketones 1 do not react with amines and sodium borohydride. In tile reactions of compounds I with hydroxyiamine, only the nitroxyl group was reduced to the hydroxylamino group, while the carbonyl group remained intact. 5 Only under rather severe conditions, viz., upon refluxing of enaminoketones 1 with hydroxylamine hydrochloride in pyridine, did the keto group also enter into the reaction: however, the heterocycle was initially cleaved and the subsequent reaction of the hydroxylamino group with the carbonyl group occurred as an imramolecular process to form pyrroline derivative 4 (Scheme 1). 3 Therefore, the addition of a nucleophile at the carbonyl group is less probable than the nucleophilic attack on the carbon atom bound to the nitrogen atom.Previously, we have demonstrated that in the reactions of enaminoketones 1 with hypohalogenites in an aqueous-methanolic solution at 0 ~ the enaminoketone group was readily cleaved to form halomethyl derivatives of 3-imidazolidine. 6 Apparently, the scheme of this reaction involves the initial formation of mono-or dihalogen derivatives followed by the nucleophilic attack on the carbon atom of the carbonyl group. The possibility of this reaction proceeding according to the abovementioned scheme was confirmed by the conversion of bromo-substituted enaminoketone 5 (X = Br) into bromomethyl derivative 6 (X = Br) in the reaction with sodium methoxide (Scheme 2). The somewhat surprising thing is that compound 6 (X = Br) did not further react with an excess of sodium methoxide. Note that unsubstituted enaminoketone la (R = Ph) did not react with sodium methoxide under these conditions and even

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Cited by 28 publications

References 21 publications

Roots: From carbenes to allenes and coordination polymers : Ever present never twice the same

Roots: From carbenes to allenes and coordination polymers : Ever present never twice the same

Verknüpfung koordinativ ungesättigter Kupfer(II)-Monomere via Cyano-versus Tetrazolyl-Donor/ Linkage of Coordinatively Unsaturated Copper(II) Monomers via Cyano versus Tetrazolyl Donor

Reactions of chloro-substituted enaminoketones,viz., derivatives of imidazolidine nitroxides, with sodium cyanide

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