Sterische Wechselwirkungen im Innern cyclisdier Verbindungen, 19 / Steric Interactions of Inner Atoms in Cyclic Compounds, 191

1971 ◽  
Vol 26 (9) ◽  
pp. 872-874 ◽  
Author(s):  
Fritz Vögtle ◽  
Rainer Lichtenthaler
Keyword(s):  
Nmr Spectra ◽  
Conformational Mobility ◽  
Steric Interactions ◽  
H Nmr ◽  
Cyclic Compounds ◽  
New Compounds

The synthesis of a series of new heterocyclic [3.3] metacyclophanes has been carried out. The 1H-NMR-spectra of the new compounds have been studied with regard to configurational problems and conformational mobility.

Chemie polyfunktioneller Liganden, 64 [1]. Über Hydridoiridium(III)-Komplexe des N.N-Bis(diphenylphosphino)-p-tolylamiii Chemistry of Polyfunctional Ligands, 64 [1]. On Hydridoiridium(III) Complexes of N,N-Bis(diphenylphosphino)-p-tolylamine

1981 ◽  
Vol 36 (5) ◽  
pp. 571-577 ◽  
Author(s):  
Jochen Ellermann ◽  
Leo Mader ◽  
Kurt Geibel
Keyword(s):  
Nmr Spectra ◽  
Oxidative Addition ◽  
H Nmr ◽  
New Compounds

H2 reacts with [Ir{(Ph2P)2N-p-C6H4CH3}2]Cl · 3 C6H6 (1) to give cis-[Ir(H)2{(Ph2P)2N-p-C6H4CH3}2]Cl · CH2Cl2 (2a). By reaction of 2a with NaBPh4 cis-[Ir(H)2{(Ph2P)2N-p-C6H4CH3}2]BPh4 (2 b) is obtained. Refluxing of 2a in CH2Cl2 yields trans-[lr(H)2{(Ph2P)2N-p-C6H4CH3}2]Cl · 1/2 CH2Cl2 (3a), which undegoes metatheses with NaBPh4 to trans-[Ir(H)2{(Ph2P)2N-p-C6H4CH3}2]BPh4 (3b). 3a is also formed by refluxing of 1 in methanol in the presence of oxygen. Oxidative addition of HCl to 1 and reaction with NaBPh4 yields trans-[Ir(H)(Cl){(Ph2P)2N-p-C6H4CH3}2]BPh4 (4b). The new compounds are characterised by their IR, Raman, 31P{1H} PFT and 1H NMR Spectra

scholarly journals New Synthetic Routes for 1-Benzyl-1,4,7,10-tetraazacyclododecane and 1,4,7,10-Tetraazacyclododecane-1-acetic Acid Ethyl Ester, Important Starting Materials for Metal-coded DOTA-Based Affinity Tags

2007 ◽  
Vol 62 (3) ◽  
pp. 397-406 ◽  
Author(s):  
Stephan W. Kohl ◽  
Katharina Kuse ◽  
Markus Hummert ◽  
Herbert Schumann ◽  
Clemens Mügge ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Ester ◽  
Nmr Spectra ◽  
Acid Ethyl Ester ◽  
Affinity Tags ◽  
X Ray ◽  
H Nmr ◽  
Synthetic Routes ◽  
New Compounds ◽  
C Nmr

Two improved routes to synthesize 1-benzyl-1,4,7,10-tetraazacyclododecane (6) and 1,4,7,10- tetraazacyclododecane-1-acetic acid ethyl ester (11) are described as well as the synthesis of 1-{2-[4-(maleimido-N-propylacetamidobutyl)amino]-2-oxoethyl}-1,4,7,10-tetraazacyclododecane- 4,7,10-triacetic acid (17) and its Y, Ho, Tm, and Lu complexes. The 1H and 13C NMR spectra of the new compounds as well as the single crystal X-ray structure analyses of the intermediates 4-benzyl-1,7-bis(p-toluenesulfonyl)diethylenetriamine (3) and 1,4,7-tris(p-toluenesulfonyl)diethylenetriamine (7) are reported and discussed. The rare earth complexes of 17 have been characterized by 1H NMR spectroscopy and MALDI-TOF mass spectrometry.

Synthese und Eigenschaften von Alkyloxi-und Aryloxi-substituierten Trithiadiborolanen / Synthesis and Properties of Alkoxi and Aryloxi Substituted Trithiadiborolanes

1981 ◽  
Vol 36 (11) ◽  
pp. 1444-1450 ◽  
Author(s):  
Max Schmidt ◽  
Erich Sametschek
Keyword(s):  
Thermal Stability ◽  
Nmr Spectra ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
H Nmr ◽  
New Compounds ◽  
Physical And Chemical ◽  
Thermal Stability Of ◽  
And Chemical Properties

Abstract The first examples of the hitherto unknown 1,2,4-Trithia-3,5-diborolanes with B-O-C-bonds have been synthesized and characterised. The diiodo substituted ring (2) reacts with 2,6-dimethylphenol, to form 3,5-bis-(2,6-dimethylphenyloxi)-1,2,4-trithia-3,5-di-borolane (3) and HI. 3,5-Diethoxi-1,2,4-trithia-3,5-diborolane, 5, and C2H5I are formed via the cleavage of diethylether by 2. From 2 and diisopropylether, the corresponding 3,5-diisopropyloxi-1,2,4-trithia-3,5-diborolane (6) is formed. The unsymmetrical ethers methyl-t-butylether and methylphenylether undergo reactions with 2 resulting in the formation of 3,5-dimethyloxi-1,2,4-trithia-3,5-diborolane (8) (besides t-C4H9I) and 3,5-diphenyloxi-1,2,4-trithia-3,5-diborolane (10) (besides CH3I). The thermal stability of the new compounds is increasing with increasing size of R in the -OR group and from aliphatic to aromatic R in this group. IR, Raman, 1H NMR and 11B NMR spectra of the compounds are reported as well as some physical and chemical properties.

scholarly journals Komplexchemie polyfunktioneller Liganden, 52 [1]. Hydrido- und Deuterido-mangan(I)-carbonyl-Komplexe des 1.1.1- Tris (diphenylphosphinomeihy 1) ethans / Complex Chemistry of Polyfiinctional Ligands, 52 [1]. Hydrido- and Deuterido-manganese(I)-carbonyl Complexes of 1,1,1 -Tris(diphenylphosphinomethyl)ethane

1979 ◽  
Vol 34 (6) ◽  
pp. 799-804 ◽  
Author(s):  
Jochen Eilermann ◽  
Helmut A. Lindner
Keyword(s):  
Uv Irradiation ◽  
Methyl Alcohol ◽  
Ultraviolet Irradiation ◽  
Nmr Spectra ◽  
Carbonyl Complexes ◽  
Decomposition Products ◽  
H Nmr ◽  
Acetone Water ◽  
Complex Chemistry ◽  
New Compounds

[Mn(CO)3(R2PCH2)3CCH3]ClO4 (1a) (R = C6H5) reacts with NaBH4 on UV irradiation to yield HMn(CO)2(R2PCH2)3CCH3 (2a). [Mn(CO)3(R2PCH2)3CCH3]BR4 (1b) gives only decomposition products. Boiling of 1a or b and NaOH in acetone/water does nots give 2a but the new hydride HMn(CO)3(R2PCH2)2C(CH3)CH2PR2 (3a). This compound cannot be prepared on ultraviolet irradiation of a solution of 1a or b and NaBH4 in methyl alcohol or acetone. The analogous deutendes DMn(CO)2(R2)PCH2)3CCH3 (2b) and DMn(CO)3(R2PCH2)2C(CH3)CH2PR2 (3b) were also prepared. The new compounds were characterized by their IR, Raman, 1H NMR and 31P NMR spectra.

Siliciumverbindungen mit starken intramolekularen sterischen Wechselwirkungen, VII [1]. Tri-tert-butylsiliciumpseudohalogenide / Silicon Compounds with Strong Intramolecular Steric Interactions, VII [1]. Tri-tert-butylsilicon Pseudohalides

1978 ◽  
Vol 33 (12) ◽  
pp. 1465-1467 ◽  
Author(s):  
Manfred Weidenbruch ◽  
Helge Pesel
Keyword(s):  
Crown Ether ◽  
Mass Spectra ◽  
Steric Interactions ◽  
Silicon Compounds ◽  
H Nmr ◽  
Pseudo Halides ◽  
New Compounds

Abstract Tri-tert-butylchlorosilane reacts with potassium pseudohalides in the presence of catalytic amounts of the crown ether 18-crown-6 to give the tri-tert-butylsilicon pseudo-halides (t-C4H9)3SiX (X = CN, NCO, NCS, N3) in good yields. These new compounds are characterized by IR, 1H NMR, and mass spectra. In the absence of the crown ether no reaction occurs. Treating tri-tert-butylsilane with AgX (X = CN, SCN) gives the silicon pseudohalides in low yields.

Preparation and polymerization of 3-(2-adamantyl)-3-methyl-2-azetidinone

1985 ◽  
Vol 50 (2) ◽  
pp. 454-458
Author(s):  
Jan Hauer ◽  
Jan Šebenda
Keyword(s):  
Melting Temperature ◽  
Intrinsic Viscosity ◽  
Anionic Polymerization ◽  
Nmr Spectra ◽  
H Nmr ◽  
New Compounds

3-(2-Adamantyl)-3-methyl-2-azetidinone (VI) was prepared, and new compounds, namely, methyl 2-(2-adamantyl) cyanoacetate, methyl-2-(2-adamantyl)-2-cyanopropanoate and methyl-2-(2-adamantyl)-2-methyl-3-aminopropanoate, were prepared in the course of the synthesis as intermediates. The anionic polymerization of lactam VI gave a polymer which was characterized by intrinsic viscosity, solubility, melting temperature and its IR and 1H NMR spectra. Compared with 3-butyl-3-methyl-2-azetidinone, lactam VI polymerizes much more slowly.

Diels-Alder Reactions of [1]Benzothieno[3,2-b]furan

1998 ◽  
Vol 63 (5) ◽  
pp. 681-697 ◽  
Author(s):  
Pavel Pihera ◽  
Jaroslav Paleček ◽  
Jiří Svoboda
Keyword(s):  
Nmr Spectra ◽  
Diels Alder ◽  
H Nmr ◽  
New Compounds

[1]Benzothieno[3,2-b]furan reacts with substituted dienes 2 as a dienophile under formation of substituted tetrahydro[1]benzothieno[3,2-b][1]benzofuran derivatives 3-14. The cycloaddition is endo-stereoselective. Aromatization of the products leads to a series of new fused [1]benzothieno[3,2-b][1]benzofurans 17-24. The 1H NMR spectra of the new compounds were fully assigned.

SOME DIRECTIONS IN THE MODIFICATION OF AZOLES

2020 ◽  
Vol 5 (443) ◽  
pp. 85-91
Author(s):  
Ibrayev M.K., ◽  
◽  
Takibayeva A.T., ◽  
Fazylov S.D., ◽  
Rakhimberlinova Zh.B., ◽  
...  
Keyword(s):  
13C Nmr Spectroscopy ◽  
Biologically Active Compounds ◽  
Biologically Active ◽  
Active Compounds ◽  
Synthesis Conditions ◽  
Alkaloid Cytisine ◽  
Azole Ring ◽  
Cyclic Compounds ◽  
New Compounds ◽  
Derivatives Of

This article presents studies on the targeted search for new derivatives of azoles, such as benzthiazole, 3,5-dimethylpyrazole, 1,3,4-oxadiazole-2-thione, 1,3,4-thiadiazole. The possibility of combining in one molecule of the azole ring with other cyclic compounds: the alkaloid cytisine, morpholine, furan and some arenes has been studied. To obtain new compounds, the reactions of bromination, acylation, and interaction with isothiocyanates were studied. Optimal synthesis conditions were studied for all reactions. It was found that the reaction of 4-bromo-3,5-dimethylpyrazole with isothiocyanates, in contrast to the previously written derivatives of anilines, takes a longer time and requires heating the reaction mixture. The combination of a pirasol fragment with halide substituents often results in an enhanced therapeutic effect. The synthesized 2-bromine-N-(6-rodanbenzo[d]thiazole-2-yl)acetamide, due to the alkylbromide group, is an important synth in the synthesis of new benzthiazole derivatives. Its derivatives combine in one molecule the rest of rhodanbenzthiazole with alkaloid cytisine and biogenic amine morpholine and are potentially biologically active compounds, since the molecule structure contains several pharmacophoric fragments: benzthiazole and alkaloid (amine) heterocycles, rhodane and urea groups. The mechanism of formation of 1,3,4-oxadiazole-2-tyons from hydrazides under action on them by carbon disulfide was studied and assumed. It was shown that dithiocarbamates in acidic medium decompose with the release of hydrogen sulfide and the formation of highly reactive isothiocyanate group. Then, intra-molecular cyclization occurs, with the formation of end products - 1,3,4-oxadiazole-2-thions. The structures of the synthesized compounds were studied by 1H and 13C NMR spectroscopy. All synthesized substances are potentially biologically active compounds, since they contain several pharmacophore fragments in their structure.

Conformational structure of ethylene glycol dibenzoate. Vibrational and NMR spectra

1981 ◽  
Vol 46 (8) ◽  
pp. 1913-1929 ◽  
Author(s):  
Bohdan Schneider ◽  
Pavel Sedláček ◽  
Jan Štokr ◽  
Danica Doskočilová ◽  
Jan Lövy
Keyword(s):  
Ethylene Glycol ◽  
Vibrational Spectra ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Conformational Structure ◽  
Infrared And Raman Spectra ◽  
H Nmr ◽  
Liquid States ◽  
Crystalline Forms ◽  
C Nmr

It was found that three crystalline forms of ethylene glycol dibenzoate can be prepared. Infrared and Raman spectra of these three forms, as well as of the glassy and liquid states, were measured. From 3JHH coupling constants obtained by analysis of the 13C satellite band of the -CH2- group in 1H NMR spectra, and from the 3JCH coupling constants of the -CO.O.CH2- fragment obtained by analysis of the carbonyl band in 13C NMR spectra it was found that in the liquid state the -CH2-CH2- group exists predominantly in the gauche conformational structure, and the bonds C-O-C-C assume predominantly a trans orientation. The results of the analysis of NMR and vibrational spectra were used for the structural interpretation of conformationally sensitive bands in vibrational spectra of ethylene glycol dibenzoate.

Preparation and absolute configuration at C(20) of 21-nor-5α-chol-22-en-24→20-olide derivatives

1981 ◽  
Vol 46 (4) ◽  
pp. 917-925 ◽  
Author(s):  
Vladimír Pouzar ◽  
Miroslav Havel
Keyword(s):  
Absolute Configuration ◽  
Nmr Spectra ◽  
Lithium Salt ◽  
H Nmr ◽  
Chemical Correlation ◽  
Unsaturated Lactones

Reaction of the aldehyde I with the lithium salt of 1-(2-tetrahydropyranyloxy)-2-propyne yielded the compounds II and IV. From the compound II the lactone XII was prepared via the intermediates III and X, the lactone XVIII was prepared from the substance IV via the intermediates V and XVI. The unsaturated lactones XII and XVIII were also prepared by sulfenylation and dehydrosulfenylation of the saturated lactones XIII and XIX. Based on chemical correlation and 1H-NMR spectra analyses of the compounds II and IV, the lactone XII was assigned the 20R-configuration whereas the lactone XVIII was allotted the 20S-configuration.

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