X-ray diffraction, multidimensional NMR spectroscopy, and MM2* calculations on chiral allyl complexes of palladium(II)

3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) reacts with acetic anhydride in pyridine under very mild conditions affording β-lactone IVa and γ-lactones Va and VIIa as condensation products. On reaction with pyridine, lactones Va and VIIa undergo elimination of acetic acid to give unsaturated lactones VIIIa and IXa, respectively. Similarly, the condensation of 20β,28-epoxy-21,22-dioxo-18α,19βH-ursan-3β-yl acetate (IIIb) with acetic anhydride leads to β-lactone IVb and γ-lactone Vb; the latter on heating with pyridine affords unsaturated lactone VIIIb and 21-methylene-22-ketone Xb. The structure of the obtained compounds was derived using spectral methods, particularly 1H and 13C NMR spectroscopy; structure of lactone IVa was confirmed by X-ray diffraction.

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Unusual Rearrangement of Naphthalene in the Synthesis of a Novel B8-B8-Bridged Derivative in the [(1,2-C2B9H11)2-3-Co]- Series. X-Ray Structure and 11B NMR Spectra of [8,8'-μ-(CH2-C9H6)-(1,2-C2B9H10)2-3-Co]- (CH3)4N+

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19970746 ◽

1997 ◽

Vol 62 (5) ◽

pp. 746-751 ◽

Cited By ~ 7

Author(s):

Andreas Franken ◽

Jaromír Plešek ◽

Christiane Nachtigal

Keyword(s):

Nmr Spectroscopy ◽

Single Crystal ◽

Nucleophilic Substitution ◽

Nmr Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Unusual Rearrangement ◽

Multinuclear Nmr Spectroscopy ◽

11B Nmr ◽

Isolated Compound

On treatment of the [(1,2-C2B9H11)2Co]- ion with naphthalene in presence of AlCl3 a remarkably bridged [8,8'-μ-(CH2-C9H6)-(1,2-C2B9H10)2-3-Co]- ion is obtained as a single isolated compound. The triatomic -CH2-C9H6- bridge is derived from the rearranged naphthalene nucleus. The mechanism of this reaction is obscure but it does resemble the "Electrophile-Induced Nucleophilic Substitution" reported earlier. The structure of the compound was established by multinuclear NMR spectroscopy and by single crystal X-ray diffraction.

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Ten-Vertex Polyhedral Monocarbaborane Chemistry. The Novel High-Yield Formation of the Ten-Vertex closo Compound [6-(PMe2Ph)-closo-1-CB9H9] from the Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11]

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19932924 ◽

1993 ◽

Vol 58 (12) ◽

pp. 2924-2935 ◽

Cited By ~ 8

Author(s):

Jane H. Jones ◽

Bohumil Štíbr ◽

John D. Kennedy ◽

Mark Thornton-Pett

Keyword(s):

Nmr Spectroscopy ◽

Diffraction Analysis ◽

High Yield ◽

Monoclinic Space Group ◽

The Novel ◽

X Ray Diffraction ◽

Metal Centre ◽

X Ray ◽

Yield Formation ◽

Boiling Toluene

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.

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Equilibrium,1H and13C NMR Spectroscopy, and X-ray Diffraction Studies on the Complexes Bi(DOTA)-and Bi(DO3A-Bu)

Inorganic Chemistry ◽

10.1021/ic0261272 ◽

2003 ◽

Vol 42 (7) ◽

pp. 2342-2349 ◽

Cited By ~ 32

Author(s):

Éva Csajbók ◽

Zsolt Baranyai ◽

István Bányai ◽

Ernő Brücher ◽

Róbert Király ◽

...

Keyword(s):

Nmr Spectroscopy ◽

X Ray Diffraction ◽

1H And13c Nmr ◽

X Ray ◽

1H And13c Nmr Spectroscopy

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Aliphatic 1H and 13C resonance assignments for the 26-10 antibody VL domain derived from heteronuclear multidimensional NMR spectroscopy

Journal of Biomolecular NMR ◽

10.1007/bf00242474 ◽

1993 ◽

Vol 3 (1) ◽

Cited By ~ 16

Author(s):

KeithL. Constantine ◽

Valentina Goldfarb ◽

Michael Wittekind ◽

MarkS. Friedrichs ◽

James Anthony ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Resonance Assignments ◽

Multidimensional Nmr ◽

Multidimensional Nmr Spectroscopy ◽

Heteronuclear Multidimensional Nmr

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Tautomerisation in 1-(4-Methylphenylazo)naphthalen-2-ol and 2-(4-Methylphenylazo)-4-methylphenol: A Crystallographic and 13C{1H}NMR Study

Journal of Chemical Research ◽

10.1177/174751989902300304 ◽

1999 ◽

Vol 23 (3) ◽

pp. 178-179

Author(s):

Wendy I. Cross ◽

Kevin R. Flower ◽

Robin G. Pritchard

Keyword(s):

Acetic Acid ◽

Nmr Spectroscopy ◽

Resonant Frequency ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Nmr Study ◽

Acetic Acid Esters ◽

Acid Esters ◽

Equivalent Carbon

The acetic acid esters of 1-(4-methylphenylazo)naphthalen-2-ol 1 and 2-(4-methylphenylazo)-4-methylphenol 3 are prepared and characterised by single crystal X-ray diffraction studies and 13C{1H}NMR spectroscopy; the position of the C(2)13C resonance for the ester is used to predict the position of resonant frequency of the equivalent carbon in the parent alcohols and hence, calculate the position of the azo-hydrazone equilibrium in these compounds.

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Exploring the Structural Chemistry of Pyrophosphoramides: N,N′,N″,N‴-Tetraisopropylpyrophosphoramide

Chemistry ◽

10.3390/chemistry3010013 ◽

2021 ◽

Vol 3 (1) ◽

pp. 149-163

Author(s):

Duncan Micallef ◽

Liana Vella-Zarb ◽

Ulrich Baisch

Keyword(s):

Crystal Structure ◽

Mass Spectrometry ◽

Nuclear Magnetic Resonance ◽

Hydrogen Bonding ◽

Nmr Spectroscopy ◽

Ir Spectroscopy ◽

Room Temperature ◽

Intermolecular Hydrogen Bonding ◽

X Ray Diffraction ◽

X Ray

N,N′,N″,N‴-Tetraisopropylpyrophosphoramide 1 is a pyrophosphoramide with documented butyrylcholinesterase inhibition, a property shared with the more widely studied octamethylphosphoramide (Schradan). Unlike Schradan, 1 is a solid at room temperature making it one of a few known pyrophosphoramide solids. The crystal structure of 1 was determined by single-crystal X-ray diffraction and compared with that of other previously described solid pyrophosphoramides. The pyrophosphoramide discussed in this study was synthesised by reacting iso-propyl amine with pyrophosphoryl tetrachloride under anhydrous conditions. A unique supramolecular motif was observed when compared with previously published pyrophosphoramide structures having two different intermolecular hydrogen bonding synthons. Furthermore, the potential of a wider variety of supramolecular structures in which similar pyrophosphoramides can crystallise was recognised. Proton (1H) and Phosphorus 31 (31P) Nuclear Magnetic Resonance (NMR) spectroscopy, infrared (IR) spectroscopy, mass spectrometry (MS) were carried out to complete the analysis of the compound.

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