Chemische Berichte最新文献

{"title":"Fully Chlorinated N-Silyl Amides of Titanium and Tungsten","authors":"B. Schwarze, W. Milius, W. Schnick","doi":"10.5282/ubm/epub.14496","DOIUrl":"https://doi.org/10.5282/ubm/epub.14496","url":null,"abstract":"The reaction of hexachlorodisilazanyllithium (Cl3Si)2NLi (1), with TiCl4 leads selectively to the novel fully chlorinated amides (Cl3Si)2NTiCl3 (2) or [(Cl3Si)2N]2 TiCl2 (3), respectively, depending on the molar ratio of the starting materials. The analogous reaction of 1 with WCl6 yielded the amide imide Cl3SiNW(Cl3)N(SiCl3)2 (5) by elimination of SiCl4. The relative amounts of the starting materials had no effect on the formation of 5. 14/15N- and 29Si-NMR data on the starting materials and products show significantly different effects, when compared with those of analogous N-trimethylsilyl derivatives, due to the lower energy of the electrons in the NSi and NM s bonds. The crystal structure of 5 (triclinic, space group P1) was determined by X-ray structure analysis.","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73637059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Additionsreaktionen an intramolekular basenstabilisierte Ge=N- und Ge=S-Doppelbindungen","authors":"M. Veith, Astrid Detemple, V. Huch","doi":"10.22028/D291-23854","DOIUrl":"https://doi.org/10.22028/D291-23854","url":null,"abstract":"","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76165215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aminoglycoside antibiotics ― Enantiomerically pure sporamine building blocks","authors":"B. Seitz, Rainer Kühlmeyer, T. Weller, W. Meier, C. Ludin, R. Schwesinger, L. Knothe, H. Prinzbach","doi":"10.1002/CBER.19891220921","DOIUrl":"https://doi.org/10.1002/CBER.19891220921","url":null,"abstract":"Starting from the prochiral dianhydrodeoxy-epi-inositol 9 a highly efficient synthesis for rac-sannamines (1, salts, derivatives) and rac-de-O-methylsannamine (18, salt) has been developed. Key steps are two regiospecific, practically quantitative epoxide opening reactions: intramolecularly in the diepoxyurethanes 11 and intermolecularly in the epoxyurethanes rac-13. With (R)-1-phenyl-ethylamine as potential primary amino group in the second step separation of the corresponding diastereomers (16, 16′) is achieved without significant loss of material. By this route enantiomerically pure (de-O-methyl)sannamines become available in which all functionalities are protected except that to be glycosidated. Attempts for an asymmetric realization of this synthesis resulted in only very small ee(de) values. \u0000 \u0000 \u0000 \u0000Aminoglycosid-Antibiotika - Enantiomerenreine Sannamin-Bausteine \u0000 \u0000 \u0000 \u0000Ausgehend vom prochiralen Dianhydrodesoxy-epi-inosit 9 wurde eine leistungsfahige Synthese fur enantiomerenreine rac-Sannamine (1, Salze, Derivate) und rac-Des-O-methylsannamin (18, Salz) ausgearbeitet. Essentielle Schritte sind zwei regiospezifische, praktisch quantitative Epoxidoffnungen: Intramolekular in den Diepoxyurethanen 11 und intermolekular in den Epoxyurethanen rac-13. Mit (R)-1-Phenylethylamin als potentieller primarer Aminogruppe im zweiten Schritt gelingt die Diastereomerentrennung (16, 16′) ohne signifikante Verluste. Es werden direkt enantiomerenreine (Des-O-methyl)Sannamin-Derivate gewonnen, in welchen alle Substituenten bis auf die zu glycosidierende OH-Gruppe geschutzt sind. Versuche zur asymmetrischen Durchfuhrung der Synthese brachten nur bescheidene ee(de)-Werte.","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1989-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88687839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SYNTHESIS AND PROPERTIES OF SUBSTITUTED BIS(CYCLOPENTADIENYL)CALCIUM COMPOUNDS - CRYSTAL-STRUCTURE OF MONOMERIC BIS[1,3-BIS-(TRIMETHYLSILYL)CYCLOPENTADIENYL](TETRAHYDROFURAN)CALCIUM","authors":"P. Jutzi, W. Leffers, G. Müller, B. Huber","doi":"10.1002/CHIN.198932239","DOIUrl":"https://doi.org/10.1002/CHIN.198932239","url":null,"abstract":"","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1989-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86544606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vanadium(V)‐Komplexe mit OO‐ und ON‐Chelatliganden als Modelle für die Vanadium‐Koordination in Biomolekülen: Die Abhängigkeit der Abschirmung des Kernes 51V von sterischen Faktoren","authors":"Carola Weidemann, Wolfgang Priebsch, D. Rehder","doi":"10.1002/CBER.19891220205","DOIUrl":"https://doi.org/10.1002/CBER.19891220205","url":null,"abstract":"Komplexe des Vanadium(V) von Typ VO5–nNn (n = 0–2), VO6–nNn (n = 0–3) und VO7–nNn (n = 0–2) mit ein- bis funfzahnigen, Sauerstoff- und Stickstoff-funktionellen Liganden zeigen chemische Verschiebungen δ(51V) zwischen – 380 und – 750 ppm (relativ zu VOCl3), wobei die hochsten Abschirmungen in Komplexen mit Dreiringstrukturen (Peroxo- und Hydroxyl-amido-Komplexe) erreicht werden. In den Komplexen V★O(OR)- (LL)2 [LL = N-Phenylbenzylhydroxamat(1–), pbha; 8-Hydroxychinolinat(1–), oxin; 3-Hydroxy-2-methyl-4-pyronat(1–), mal] wird in der Reihe R = CH2R′, CH(R′R″), CR′(R″)2 zunehmende Abschirmung beobachtet. die Komplexe werden durch Umsetzung ein- und mehrwertiger, darunter auch cyclischer Alkohole mit [VO(oxin)2]2(μ-O) bzw. VOCl(pbha)2, oder direkt aus Vanadat und den Liganden erhalten. Chirale Alkohole (R★OH) geben Anlas zu zwei Kernresonanzsignalen fur die beiden diastereomeren Enantiomerenpaare. Die Ergebnisse der Untersuchungen in der Reihe VO(OR)(oxin)2 erlauben eine Beurteilung auch der Koordination einiger Nucleoside (R = Inosin, Uridin und 2′- Desoxyuridin). VOCl(pbha)2 kristallisiert in der monoklinen Raumgruppe P21/n mit den folgenden Zellparametern: a = 1184.3, b = 1564.1, c = 1364.4 pm; β = 91.94°. Die Koordinationsgeometrie ist verzerrt oktaedrisch; der V-O-Doppelbindungsabstand ist mit 180.1 pm bemerkenswert lang. \u0000 \u0000 \u0000 \u0000Vanadium(V) complexe with OO and ON Ligands as Models for Vanadium Coordination sites in Biomolecules: The Dependence of 51V Shielding on Streric Effects \u0000 \u0000 \u0000 \u0000Vanadium(V) complexes of the type VO5–nNn (n = 0–2), VO6–nNn (n = 0–3) und VO7–nNn (n = 0–2) containing mono to pentadentate oxygen and nitrogen ligands exhibit chemical shifts δ(51V) of – 380 to 750 ppm (relative to VOCl3) with the highest shielding found in complexes with 3-membered ring structures (peroxo and hydroxylamido complexes). In the complexes V★O(OR)(LL)2 [LL = N-phenylbenzylhydroxamate(1–), pbha; 8-hydroxychinolate(1–), oxin; 3-hydroxy-2-methyl-4-pyronate (1–), mal], shielding increases in the order CH2R′, CH(R′R″), CR′(R″)2. The compounds were obtained from the reaction of mono- and polyhydric (including cyclic) alcohols with [VO-(oxin)2]2(μ-O) or VOCl(pbha)2, or directly from vanadate and the ligands. Chiral alcohols (R★OH) give rise to two resonance signals corresponding to the two diastereomeric pairs of enantiomers. The findings from the complex series VO(OR)(oxin)2 also allow for the assessment of the mode of coordination of several nucleosides (R = inosine, uridine and 2′-deoxyuridine). VOCl(pbha)2 crystallizes in the monoclinic space group P21/n with the following cell parameters: a = 1184.3, b = 1564.1, c = 1364.4 pm; β = 91.94°. The coordination geometry is distorted octahedral; the VO double bond (180.1 pm) is remarkably long.","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80651603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Übergangsmetall‐Silyl‐Komplexe, 27. Silylsubstituierte Hetero‐Mehrkern‐Komplexe durch Umsetzung der anionischen Silyl‐Komplexe [MeCpMn(CO)2SiR3]− und [Fe(CO)3(PPh3)SiR3]− mit Zink‐, Cadmium‐ und Quecksilber‐Dihalogeniden","authors":"Erika Kunz, U. Schubert","doi":"10.1002/CBER.19891220204","DOIUrl":"https://doi.org/10.1002/CBER.19891220204","url":null,"abstract":"Die anionischen Silyl-Komplexe [MeCpMn(CO)2SiMePh2]− (1) und [Fe(CO)3(PPh3)SiR3]− (4) reagieren mit aquimolaren Mengen ZnCl2, CdCl2 oder HgBr2 zu den Zweikern-Komplexen MeCpMn(CO)2(SiMePh2)MX (2; MX = ZnCl, CdCl oder HgBr) bzw. Fe(CO)3(PPh3)(SiR3)MX (5; MX = CdCl oder HgBr); der FeZn-Komplex ist instabil. Umsetzung der Komplexe 2 und 5 mit einem weiteren Aquivalent 1 bzw. 4 ergibt die symmetrischen Dreikern-Komplexe [MeCpMn(CO)2(SiMePh2)]2M (3; M = Cd, Hg) und [Fe(CO)3(PPh3)]2Hg (6) bzw. den unsymmetrischen Dreikern-Komplex MeCp(CO)2(Ph2MeSi)MnHgFe(CO)3-(PPh3)(SiR3) (7). Die symmetrischen Komplexe mit MnZnMn- bzw. FeCdFe-Bindung werden vermutlich aus sterischen Grunden nicht gebildet. Mit uberschussigem Quecksilberhalogenid reagieren 3 (M = Hg) und 6 unter Halogensilan-Abspaltung. \u0000 \u0000 \u0000 \u0000Transition-Metal Silyl complexes, 27. Silyl-Substituted Heteromultinuclear Complexes by Reaction of the Anionic Silyl Complexes [MeCpMn(CO)2SiR3]− and [Fe(CO)3(PPh3)SiR3]− with Dihalides of Zinc, Cadmium, or Mercury \u0000 \u0000 \u0000 \u0000The anionic silyl complexes [MeCpMn(CO)2SiMePh2]− (1) and [Fe(CO)3(PPh3)SiR3]− (4) react with equimolar amounts of ZnCl2, CdCl2, or HgBr2 to give the dinuclear complexes MeCpMn(CO)2(SiMePh2)MX (2; MX = ZnCl, CdCl, or HgBr) or Fe(CO)3(PPh3)MX (5; MX = CdCl or HgBr); the FeZn complex is unstable. Reaction of 2 and 5 with a second equivalent of 1 or 4 yields the symmetrical trinuclear complexes [MeCpMn(CO)2(SiMePh2)]2M (3; M = Cd, Hg) and [Fe(CO)3(PPh3)(SiR3)]2Hg (6) or the unsymmetrical trinuclear complex MeCp(CO)2(Ph2MeSi)MnHgFe(CO)3 (PPh3)(SiR3) (7). The symmetrical complexes containing MnZnMn or FeCdFe units are not formed, presumably for steric reasons. With an excess of mercury halides 3 (M = Hg) and 6 react by silyl halide elimination.","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82192459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photoreaktion von Hexacarbonylbis(η5-methylcyclopentadienyl)diwolfram mit konjugierten Dienen","authors":"C. G. Kreiter, G. Wendt, J. Kaub","doi":"10.1002/CBER.19891220202","DOIUrl":"https://doi.org/10.1002/CBER.19891220202","url":null,"abstract":"Hexacarbonylbis(η5-methylcyclopentadienyl)diwolfram (1) und 1,3-Butadien (2) reagieren photochemisch bei 253 K in n-Pentan unter CO-Abspaltung und 1,4-H-Verschiebung zu (μ-η1:3-2-Buten-1-yliden)tetracarbonylbis(η5-methylcyclopentadienyl)diwolfram (8). Unter den gleichen Bedingungen ergeben 2-Methyl-1,3-butadien (3), 2,3-Dimethyl-1,3-butadien (4) bzw. 1,3-Cyclohexadien (5) die Dicarbonyl(μ-η1:2-carbonyl)(η4-dien)bis(η5-methylcyclopentadienyl)diwolfram-Komplexe 9, 10 und 11 mit 4-Elektronen-COBruckenliganden. Dagegen entsteht mit 1,3,5-Cycloheptatrien (6) Dicarbonyl(η3-2,4-cycloheptadien-1-yl)(η5-methylcyclopentadienyl)wolfram (12). Als Nebenprodukt fallt bei allen Reaktionen Tetracarbonylbis(η5-methylcyclopentadienyl)-diwolfram (7) an. Die Komplexe 9–11 zeigen einen gehinderten intramolekularen Austausch der Carbonyl-Liganden mit Aktivierungsbarrieren von ΔG≠303 = 60.2 ± 6 (9), ΔG≠313 = 62.4 ± 1 (10) und ΔG≠313 = 60.8 ± 2 (11) kJ/mol. Die Komplexe 8–12 wurden durch ihre IR-Spektren im v(CO)-Bereich und durch 1H-NMR-Spektren charakterisiert. Die Kristall- und Molekulstruktur von 8 wurde durch eine Rontgen-Strukturanalyse bestimmt. \u0000 \u0000 \u0000 \u0000Photoreaction of Hexacarbonylbis(η5-methylcyclopentadienyl)ditungsten with Conjugated Dienes \u0000 \u0000 \u0000 \u0000Hexacarbonylbis(η5-methylcyclopentadienyl)ditungsten (1) and 1,3-butadiene (2) react photochemically at 253 K in n-pentane by CO elimination and 1,4-H shift to (μ-η1:3-2-buten-1-ylidene)tetracarbonylbis(η5-methylcyclopentadienyl)ditungsten (8). Under the same conditions, 2-methyl-1-3-butadiene (3), 2,3-dimethyl-1,3-butadiene (4), and 1,3-cyclohexadiene (5) yield the dicarbonyl(μ-η1:2-carbonyl)(η4diene)bis(η5-methylcyclopentadienyl)ditungsten complexes 9, 10 and 11, respectively with 4-electron CO bridging ligands. In contrast, with 1,3,5-cycloheptatriene (6), dicarbonyl(η3-2,4-cycloheptadien-1-yl)(η5-methylcyclopentadienyl)tungsten (12) is formed. Byproduct of all reactions is tetracarbonylbis(η5-methylcyclopentadienyl)ditungsten (7). The complexes 9–11 show a hindered intramolecular exchange of the carbonyl ligands with barriers of activation of ΔG≠303 = 60.2 ± 6 (9), ΔG≠313 = 62.4 ± 1 (10) und ΔG≠313 = 60.8 ± 2 (11) kJ/mol. The complexes 8–12 were characterized by their IR spectra in the v(CO) region and by 1H-NMR spectra. The crystal and molecular structure of 8 was determined by an X-ray structure analysis.","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76123906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Übergangsmetall-Silyl-Komplexe, 26. Gold(I)-Silyl-Komplexe","authors":"Jürgen Meyer, J. Willnecker, U. Schubert","doi":"10.1002/CBER.19891220203","DOIUrl":"https://doi.org/10.1002/CBER.19891220203","url":null,"abstract":"Komplexe des Typs L-Au-SiR3 mit L = PR′3 oder PhNC und SiR3 = Si(aryl)3, Si(SiMe3)3 oder SiPh2Me wurden durch Umsetzung von L-Au-Cl mit LiSiR3 dargestellt. Ihre Stabilitat sinkt in Abhangigkeit von L und R in der Reihenfolge R′3P-Au-Si(aryl)3 > R′3P-Au-Si(SiMe3)3 > R′3P-Au-SiPh2Me ≈ PhNC-Au-SiR3. Umsetzung von R′3P-Au-CH3 oder R′3P-Au-OAc mit HSiR3 ergibt keine Silyl-Komplexe, bei Verwendung chlorierter Silane, HSi-R2Cl, findet lediglich CH3/Cl− bzw. OAc/Cl-Austausch statt. Das Mosbauer-Spektrum von MePh2P-Au-SiPh3 (6) sowie NMR- und IR-spektroskopische Untersuchungen zeigen, das Silylreste als starke σ-Donor-Liganden gegenuber dem Goldatom wirken. MePh2P-Au-SiPh3 (6) und MePh2P-Au-Si(SiMe3)3 (7) wurden durch Rontgenstrukturanalysen charakterisiert [AuSi 235.4(4) und 235.6(2) pm]. Die AuSi-Bindung in MePh2P-Au-SiPh2 Tol (5) wird durch X2 (X = Cl, Br, I), HCl oder MeI, nicht aber durch H2O oder MeOH gespalten.","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88063949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RADICAL IONS AND PHOTOCHEMICAL CHARGE-TRANSFER PHENOMENA .16. PHOTOREACTIONS OF BIACETYL WITH ELECTRON-RICH OLEFINS - AN EXTENDED MECHANISM","authors":"J. Mattay, J. Gersdorf, K. Buchkremer","doi":"10.1002/CHIN.198725077","DOIUrl":"https://doi.org/10.1002/CHIN.198725077","url":null,"abstract":"","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85447876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[On the structure of nardosinon. I. Functional groups and dedection of a protion of the structure from the NMR spectrum].","authors":"G Rücker","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":9792,"journal":{"name":"Chemische Berichte","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1969-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16877740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}