Unique Digoldgermanes: Structural Characteristics, Dynamic Behaviour and Distinctive Reactions

Abstract Digoldgermanes with a gold coordinated by a dialkylgermylene ligand, R’2Ge(AuPR3)(AuGeR’2) (3a; R = Me, 3b; R = Et), were synthesized as green solids through the reactions of stable dialkylgermylene 1 with R3PAuCl followed by the reduction with KC8 at ambient temperatures. The structural characteristics of 3a and 3b were elucidated using NMR spectroscopy, X-ray crystallography, and DFT calculations. An intense absorption maximum was observed at 590 nm in the UV-vis spectrum of 3a in hexane. A pendular motion of AuPR3 group between Ge(IV) and Ge(II) of 3a and 3b occurring in the NMR time scale was found by the dynamic 1H NMR analysis, suggesting that the Ge(II) ligand has an enhanced electrophilicity to be attacked by the nucleophilic gold atom which closes to ‒1 oxidation state. DFT calculations of 3a revealed the existence of high-lying σ(Ge-Au) type HOMO and low-lying LUMO with germylene pπ nature. We show the bond formation and activation alternatively at Au or Ge atom, a methylation of digoldgermane 3a with MeOTf affords methylgermane 5. Moreover, the digoldgermane 3a reacts with Cl− ion of Ph4PCl and CH3C(O)Cl smoothly to form the corresponding chloride-addition product 7 and chlorogoldgermane 9, respectively. Cyclic trimerization reactions of aromatic isocyanates were high-efficiently catalyzed by 3a giving the corresponding 1,3,5-triaryl isocyanurates.

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Dynamic stereoisomerization in inherently chiral bimetallic [2]catenanes

Chemical Communications ◽

10.1039/c4cc07392d ◽

2015 ◽

Vol 51 (27) ◽

pp. 5840-5843 ◽

Cited By ~ 13

Author(s):

Thirumurugan Prakasam ◽

Matteo Lusi ◽

Elisa Nauha ◽

John-Carl Olsen ◽

Mohamadou Sy ◽

...

Keyword(s):

Dft Calculations ◽

Variable Temperature ◽

Redox Processes ◽

Metal Translocation ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Inherently Chiral

Stereoisomerization and the unprecedented phenomenon of metal translocation in the absence of redox processes were probed in two inherently chiral bimetallic [2]catenanes by using a combination of variable-temperature 1H NMR and CD spectroscopies, X-ray crystallography, and DFT calculations.

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Synthesis, characterization, and protonation of octaethylporphyrin osmium nitrosyl complexes containing axial thiolate ligands - X-ray structures of an alkyl thionitrite (RSNO) and its (OEP)Os(NO)(SR) addition product

Canadian Journal of Chemistry ◽

10.1139/v00-168 ◽

2001 ◽

Vol 79 (5-6) ◽

pp. 830-840 ◽

Cited By ~ 13

Author(s):

Jonghyuk Lee ◽

Geun-Bae Yi ◽

Douglas R Powell ◽

Masood A Khan ◽

George B Richter-Addo

Keyword(s):

Addition Product ◽

Molecular Structures ◽

Sequential Reaction ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Vis Spectroscopy ◽

Sh Group ◽

Cationic Compounds ◽

No Scr

The (OEP)Os(NO)(SR) compounds (R = Me, Et, i-Pr, t-Bu) have been prepared in 33-48% isolated yields by the formal trans-addition of the precursor alkyl thionitrites (RSNO) across the metal center in (OEP)Os(CO). The nitrosyl thiolate compounds have been characterized by IR, 1H NMR, and UV-vis spectroscopy, and by FAB mass spectrometry. Their IR spectra display bands in the 1751-1755 cm-1 (KBr) range, which is indicative of terminal N-bound NO ligands in this class of compounds. The thiolate-thiol (OEP)Os(NO)(SCH2CH2SH) complex has been prepared in 70% isolated yield from the reaction of (OEP)Os(NO)(O-i-C5H11) with ethane-1,2-dithiol. Nitrosation of the free -SH group in (OEP)Os(NO)(SCH2CH2SH) with t-BuONO, followed by reaction with (TTP)Ru(CO) gave [(OEP)Os(NO)](µ-SCH2CH2S-S,S')[Ru(NO)(TTP)] in 70% yield by 1H NMR spectroscopy. The (OEP)Os(NO)(SCR'2CH2NHC(O)Me) compounds have also been prepared either by an alkoxide-thiolate exchange reaction (for R' = H) or by RSNO addition to (OEP)Os(CO) (for R' = Me). The solid-state molecular structures of the precursor RSNO thionitrite (for R' = Me) and the metalloderivative have been determined by single-crystal X-ray crystallography. Protonation of these (OEP)Os(NO)(SCR'2CH2NHC(O)Me) complexes gave the amide-bound [(OEP)Os(NO)(O=C(Me)NHCH2CR'2SH)]BF4 derivatives. The latter cationic compounds were also obtained by the sequential reaction of (OEP)Os(CO) with nitrosonium tetrafluoroborate, followed by addition of the amide-thiol reagent. Key words: thionitrite, nitrosothiol, porphyrin, X-ray structure, nitric oxide, osmium.

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Supramoleküle aus Kronenethern und geminalen Sulfonen: Synthese von vier binären Komplexen und Kristallstruktur von (CH2CH2O)4·2H 2C(SO2C2H5)2/Supramolecules of Crown Ethers with Geminal Sulfones: Synthesis of Four Binary Complexes and Crystal Structure of (CH2CH2O )4·2H2C(SO2C2H5)2

Zeitschrift für Naturforschung B ◽

10.1515/znb-1995-0705 ◽

1995 ◽

Vol 50 (7) ◽

pp. 1018-1024 ◽

Cited By ~ 2

Author(s):

Axel Michalides ◽

Dagmar Henschel ◽

Armand Blaschette ◽

Peter G. Jones

Keyword(s):

Monoclinic Space Group ◽

Triclinic Space Group ◽

Space Group ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Binary Complexes ◽

Cyclic Polyethers ◽

Adjacent Unit ◽

Methylene Group

In a systematic search for supramolecular complexes involving all combinations of the cyclic polyethers 12-crown-4 (12C4), 15-crown-5 (15C 5), 18-crown-6 (18C 6) and dibenzo- 18-crown-6 (DB -18C6), and the geminal di- or trisulfones H2C(SO 2Me)2, H2C (SO2Et)2 and HC (SO2Me)3-n (SO2Et)n (n = 0 -3 ) , only the following four complexes could be isolated and unequivocally characterized by elemental analysis and 1H NMR spectroscopy: [(12C4){H2C (SO2Et)2}2] (3), [(18C6){H2C (S O2Me)2}] (4), [(DB -18C 6){H2C (SO2Et)2}] (5) and [(D B -18C 6)2{HC (SO2Me )(SO2Et)2}3] (6). The structure of 3 (triclinic, space group P1̄) consists of crystallographically centrosymmetric formula units, in which the disulfone molecules are bonded on each side of the ring by two C -H ··· O(crown) interactions originating from the central methylene group (H···O 213 pm) and from the methylene group of one EtSO2 moiety ( H ··· O 237 pm). Formula units related by translation are connected into parallel strands by a third type of reciprocal C -H ···O bond (H ···O 232 pm) between the second H atom of the central methylene group and a sulfonyl oxygen atom of the adjacent unit. The structure of 4 (monoclinic, space group C2/c) showed severe disorder of the crown ether and could not be refined satisfactorily. Compounds 5 and 6 crystallized as long and extremely thin fibres, indicative of linear-polymeric supramolecular structures; single crystals for X-ray crystallography were not available.

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Configurational and conformational studies on condensation products of biogenic amines with 2,5-anhydro-D-mannose

Canadian Journal of Chemistry ◽

10.1139/v85-483 ◽

1985 ◽

Vol 63 (11) ◽

pp. 2915-2921 ◽

Cited By ~ 7

Author(s):

Ian M. Piper ◽

David B. MacLean ◽

Romolo Faggiani ◽

Colin J. L. Lock ◽

Walter A. Szarek

Keyword(s):

Hydrogen Bond ◽

Intermolecular Hydrogen Bond ◽

Direct Methods ◽

Conformational Studies ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Twist Conformation ◽

Cell Dimensions ◽

Internal Hydrogen Bond

The products of a Pictet–Spengler condensation of tryptamine and of histamine with 2,5-anhydro-D-mannose have been studied by X-ray crystallography to establish their absolute configuration. 1(S)-(α-D-Arabinofuranosyl)-1,2,3,4-tetrahydro-β-carboline (1), C16H20N20O4, is monoclinic, P21 (No. 4), with cell dimensions a = 13.091(4), b = 5.365(1), c = 11.323(3) Å, β = 115.78(2)°, and Z = 2. 4-(α-D-Arabinofuranosyl)imidazo[4,5-c]-4,5,6,7-tetrahydropyridine (3), C11H17N3O4, is orthorhombic, P212121 (No. 19), with cell dimensions a = 8.118(2), b = 13.715(4), c = 10.963(3) Å, and Z = 4. The structures were determined by direct methods and refined to R1 = 0.0514, R2 = 0.0642 for 3210 reflections in the case of 1, and to R1 = 0.0312, R2 = 0.0335 for 1569 reflections in the case of 3. Bond lengths and angles within both molecules are normal and agree well with those observed in related structures. In 3 the base and sugar adopt a syn arrangement, which is maintained by an internal hydrogen bond between O(2′) and N(3). The sugar adopts a normal 2T3 twist conformation. The sugar has the opposite anti arrangement in the β-carboline 1 and the conformation of the sugar is unusual; it is close to an envelope conformation with O(4′) being the atom out of the plane. This conformation is caused by a strong intermolecular hydrogen bond from O(5′) in a symmetry-related molecule to O(4′). Both compounds are held together in the crystal by extensive hydrogen-bonding networks. The conformations of the compounds in solution have been investigated by 1H nmr spectroscopy, and the results obtained were compared with those obtained by X-ray crystallography for 1 and 3.

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Synthesis and characterization of a linked, π-π stacked organotin compound of 2-mercapto-6-nitrobenzothiazolyl diphenyltin chloride with 2-ethoxyl-6-nitrobenzothiazole

Canadian Journal of Chemistry ◽

10.1139/v03-087 ◽

2003 ◽

Vol 81 (7) ◽

pp. 825-831 ◽

Cited By ~ 13

Author(s):

Chunlin Ma ◽

Qin Jiang ◽

Rufen Zhang

Keyword(s):

Title Compound ◽

Organotin Compound ◽

X Ray Diffraction ◽

X Ray ◽

Stacking Interaction ◽

X Ray Crystallography ◽

H Nmr ◽

Π Stacking ◽

Π Stacking Interaction ◽

Molecular Components

The new organotin compound, Ph2Sn(Cl)[S(C7H3N2O2S)]·[(C7H3N2O2S)OEt], assembled by an intermolecular aromatic benzothiazolebenzothiazole π-π stacking interaction, has been synthesized by the reaction of diphenyltin dichloride with 2-mercapto-6-nitrobenzothiazole. The title compound was characterized by elemental, IR, 1H NMR, and X-ray crystallography analyses. Single-crystal X-ray diffraction data reveals that the title compound has two different molecular components. The component Ph2Sn(Cl)[S(C7H3N2O2S)] has a pentacoordinate tin, which further forms an infinite one-dimensional chain by intermolecular non-bonded Cl···S interactions, resulting in an intercalation lattice that holds (C7H3N2O2S)OEt molecules. The formation of the molecule (C7H3N2O2S)OEt as well as its intercalated mechanism has also been discussed.Key words: organotin, assemble, π-π stacking interaction, 2-mercapto-6-nitrobenzothiazole, non-bonded interaction, crystal structure.

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Metallkomplexe mit biologisch wichtigen Liganden, CXLVI [1]. Bis(allyl)-N,O-α-Aminocarboxylat-Rhodium-Komplexe / Metal Complexes of Biologically Important Ligands, CXLVI [1]. Bis(allyl)-N,O-α-Aminocarboxylate-Rhodium Complexes

Zeitschrift für Naturforschung B ◽

10.1515/znb-2002-0714 ◽

2002 ◽

Vol 57 (7) ◽

pp. 810-818 ◽

Cited By ~ 2

Author(s):

Walter Ponikwar ◽

Peter Mayer ◽

Wolfgang Beck

Keyword(s):

Amino Acids ◽

Metal Complexes ◽

Dynamic Behaviour ◽

Rhodium Complexes ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr

The reactions of [(η3-C3H5)2Rh-μ-Cl]2 with the anions of α-amino acids (glycine, L-alanine, L-valine, L-isoleucine, L-proline, L-phenylalanine, L-phenylglycine, L-thyrosine) afford the N,O-chelates (η3-C3H5)2Rh(α-amino carboxylate). For complex (η3-C3H5)2Rh(glycinate) dynamic behaviour in solution could be observed by 1H NMR. The structure of (η3-C3H5)2Rh(L-prolinate) was determined by X-ray diffraction.

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[Zn(phen)2(CX3COO)]+, X = H orCl; Influence of X on the Coordination Mode of the Carboxylate Group (phen = 1,10-Phenanthroline)

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-1005 ◽

2005 ◽

Vol 60 (10) ◽

pp. 1049-1053 ◽

Cited By ~ 1

Author(s):

Zeanab Talaei ◽

Ali Morsali ◽

Ali R. Mahjoub

Keyword(s):

Nmr Spectroscopy ◽

Elemental Analysis ◽

Coordination Mode ◽

Bidentate Ligand ◽

Carboxylate Group ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Coordinate Geometry ◽

C Nmr

Two new ZnII(phen)2 complexes with trichloroacetate and acetate anions, [Zn(phen)2(CCl3COO)- (H2O)](ClO4) and [Zn(phen)2(CH3COO)](ClO4), have been synthesized and characterized by elemental analysis, IR, 1H NMR, 13C NMR spectroscopy. The single crystal X-ray data of these compounds show the Zn atoms to have six-coordinate geometry. From IR spectra and X-ray crystallography it is established that the coordination of the COO− group is different for trichloroacetate and acetate. The former acts as a monodentate whereas the latter acts as a bidentate ligand.

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