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  • 1
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition Metal Carbene Complexes, XXXVIII. Arylalkoxy-, Aryldialkylamino- and Dialkylaminoalkoxycarbenes als Ligands in Complexes of the Type Fe(CO)4Lu. v. Irradiation of cyclopentadienylmetalcarbonylnitrosyl carbene complexes of the type C5H5Mo(CO)(NO)C(R)C6H5 (1a-c, R = OCH3, OC2H5, N(CH3)2) in the presence of Fe(CO)5 results in the formation of the carbene complexes (CO)4FeC(R)C6H5 by transference of „C(R)C6H5“ . By changing the procedure which had previously been used for the preparation of carbene complexes - we excluded water and used reaction temperatures between 0° and -60° - we have been able to prepare complexes of the type (CO)4FeC-(OC2H5)R (R = C6F5, C6Cl5, N(CH3)2, N(C2H5)2). The structures of the oily or crystalline, diamagnetic complexes are unambiguously determined from the elemental analysis, and the i. r., 1H n. m. r. and mass spectra. In the case of the complex (CO)4FeC(OC2H5)N(CH3)2 the free activation enthalpy of the rotation about the Ccarben-N- and Ccarben-O bonds is 21 and 5-7 kcal/mole, respectively.
    Notes: Cyclopentadienylmetallcarbonylnitrosyl-carbenkomplexe C5H5Mo(CO)(NO)C(R)C6H5 (1a-c, R = OCH3, OC2H5, N(CH3)2) reagieren mit Fe(CO)5 bei UV-Bestrahlung unter Übertragung von „C(R)C6H5“ zu den Carbenkomplexen (CO)4FeC(R)C6H5 (3a-c). - Durch Abänderung des bisher gebräuchlichen Syntheseverfahrens für acyclische Übergangsmetallcarbonyl-Carbenkomplexe - Ausschluß von Wasser und Reaktionstemperaturen zwischen 0° und -60° - gelang es, auch auf diese Weise Verbindungen des Typs (CO)4FeC(OC2H5)R (7d-g, R = C6F5, C6Cl5, N(CH3)2, N(C2H5)2) darzustellen. Die öligen bzw. kristallinen, diamagnetischen Komplexe sind durch IR-, 1H-NMR- und massenspektroskopische Untersuchungen sowie durch analytische Befunde eindeutig gesichert. Bei dem Komplex (CO)4FeC(OC2H5)N(CH3)2 wurde die Freie Aktivierungsenthalpie der Rotation um die CCarben-N- und CCarben-O-Bindung mit 21 bzw. 5-7 kcal/Mol bestimmt.
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  • 2
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition Metal Carbyne Complexes, XVPhenylcarbyne as well as Methoxyphenyl-, (Dimethylamino)phenyl-, and Aminophenylcarbene as Ligands in Cationic or Neutral Complexes of the Type π-ArCr(CO)2LComplexes of the type π-ArCr(CO)3 1a-d are converted into the carbene complexes π-ArCr(CO)2-[C(C6H5)OCH3] 2a-d by treatment with phenyllithium followed by alkylation. On treatment with boron trichloride 2a-d yield the cationic carbyne complexes of the general formula {π-ArCr(CO)2[C(C6H5]}⊕[BCl4]⊖ 3a, c, d Aminolysis with ammonia or dimethylamine leads to the aminocarbene complexes π-ArCr(CO)2[C6H5)NR2] 4 and 5 which are not obtainable by direct aminolysis of 2a-d. These diamagnetic complexes, some of which are very thermolabile, were characterized by i. r., H n. m. r., and 13C n. m. r. spectroscopy.
    Notes: Aus Tricarbonyl-Aromaten-chrom(0)-Komplexen π-ArCr(CO)3 1a-d lassen sich durch Umsetzung mit Phenyllithium und anschließende Alkylierung die Carbenkomplexe π-ArCr(CO)2-[C(C6H5)OCH3] 2a-d darstellen, deren Reaktion mit Bortrichlorid zu kationischen Carbinkomplexen der allgemeinen Formel {π-ArCr(CO)2[C(C6H5]}⊕[BCl4]⊖ 3a, c, d führt. Bei der Aminolyse der kationischen Komplexe mit Ammoniak oder Dimethylamin entstehen - durch Aminolyse von 2a-d nicht zugängliche - Aminocarbenkomplexe π-ArCr(CO)2[C6H5)NR2] 4 und 5. Die diamagnetischen, teilweise sehr thermolabilen Verbindungen werden durch IR-, 1 H-NMR-und 13C-NMR-Spektren charakterisiert.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 3101-3107 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition Metal Carbene Complexes, XXXII Phenylalkoxycarbene as Ligand in Cyclopentadienylcarbonylnitrosyl Complexes of Chromium, Molybdenum and TungstenCyclopentadienyldicarbonylnitrosyl complexes of chromium, molybdenum and tungsten C5H5M(CO)2NO(M = Cr, Mo, W) (1a-c) add in ether one mole of phenyllithium. The formed acylmetallates are alkylated by oxonium tetrafluoroborates (4d, e) to the free carbene complexes. I.r., 1H n.m.r. and mass spectra of the stable, volatile, diamagnetic carbene complexes 5 show that the nucleophilic attack of LiC6H5 occurs only at one of the two CO-groups, and that the σ-donor/π-acceptor relationship of the different carbene ligands affects the remaining ligands bound to the central metal atom. When the complexes 5 are irradiated in the presence of iron pentacarbonyl the carbene ligand is transferred to give the corresponding (CO)4Fe-carbene complexes.
    Notes: Cyclopentadienyl-dicarbonyl-nitrosyle des Chroms, Molybdäns und Wolframs C5H5M(CO)2-NO (M = Cr, Mo, W) (1a-c) addieren in Äther äquimolare Mengen Phenyllithium. Die sich dabei bildenden Acylmetallate lassen sich durch Alkylierung mit Oxoniumtetrafluoroboraten (4d, e) zu den freien Carben-Komplexen umsetzen. IR-, 1H-NMR- und massenspektroskopische Untersuchungen der stabilen, sublimierbaren, diamagnetischen Carben-Komplexe 5 zeigen, daß der nucleophile Angriff von LiC6H5 nur an einer der beiden CO-Gruppen stattfindet und das σ-Donor/π-Akzeptor-Verhältnis der verschiedenen Carben-Liganden sich charakteristisch auf die übrigen am Zentralmetall gebundenen Liganden auswirkt. Durch Belichtung lassen sich die Carben-Liganden der Komplexe 5 auf Eisenpentacarbonyl unter Bildung der entsprechenden (CO)4Fe-carben-Komplexe übertragen.
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  • 4
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Ill.
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  • 5
    Publication Date: 2012-11-16
    Description: Abstract 2608 Background: Combined treatment with a tyrosine kinase inhibitor (TKI) and ALL-type induction and consolidation chemotherapy followed by allogeneic SCT is standard front-line therapy for younger patients with Ph+ALL, but the value of adding intensive chemotherapy to a TKI in elderly patients is controversial. More than 90% of elderly patients achieve a complete remission, irrespective of the type of TKI-based induction, but relapse is the major cause of treatment failure. In a previously reported randomized trial examining imatinib combined with intensive induction and consolidation chemotherapy for Ph+ALL in elderly patients (n=55), the probability of overall survival (OS) after 24 months was 42% ± 8% (Ottmann OG et al., Cancer. 2007; 109:2068-76). To date, very little published data on long-term outcome of elderly patients with Ph+ALL are available. Aims: We conducted the present analysis to determine whether subsets of patients derive long-term benefit from combined imatinib plus intensive chemoptherapy, examine the characteristics of long-term survivors, determine whether such patients can be identified by assessment of MRD, and obtain preliminary results on the feasibility and efficacy of SCT in this population of elderly patient. Study design and patients demographics: Our current analysis includes a total of 121 patients (119 ALL, 2 CML in lymphoid blast crisis), with a median age of 66 years (range 54–80). Fifty-five patients were enrolled in a previously reported randomized clinical trial comparing single-agent imatinib and chemotherapy as induction therapy, followed by up to 6 cycles of consolidation chemotherapy; a further 67 patients were subsequently treated according to this protocol as per recommendation by the GMALL Study Group. Results: The overall CR rate was 88%, median time to progression was 14.5 months (range 0.5–102) and OS was 18.6 months (range 0.5–102), respectively. Probabilities of remission duration, survival and TTP at 5 years were 19%, 22% and 19%, respectively. The type of initial induction therapy had no significant impact on OS and DFS. Of 113 pts, who were evaluable for comorbities, pulmonary disease was the only comorbidity associated with inferior outcome (median OS 13 months vs. 20 months, univariate analysis p=0.02). Allogeneic SCT was performed in CR1 in 12 patients and as salvage therapy in another 7 patients. Median age of these 19 patients was 62y (range 54–69). The time from diagnosis to SCT in CR1 was 4.6 months (2.9 mo – 16.8 mo) and from relapse to SCT in 〉CR1 3 months (2.1 mo – 6.1 mo). The 5yr OS in patients transplanted in CR1 vs. non-transplanted patients was superior (48% vs 22%). Remarkably, OS of the 7 patients transplanted beyond CR1 as part of salvage therapy was 43% after 4.5 years. With a median follow-up of 21.6 months (range 3.3– 54) after SCT, 8 patients are in ongoing CR with a median OS of 51.8 months from initial diagnosis (range 35 – 66), 5 pts. died in CR, 6 pts. relapsed. Conclusions: The combination of imatinib with intensive chemotherapy is feasible in elderly patients, but long-term survival is poor primarily due to high relapse rate. Allogeneic SCT in CR1 is superior to conventional therapy and should be considered as front-line therapy in this elderly patient population. The encouraging results of allogeneic SCT performed beyond CR1 suggest that SCT should be considered as definite postremission therapy in a larger proportion of elderly patients than is current practice. Disclosures: Ottmann: Novartis: Honoraria, Research Funding; BMS: Honoraria, Research Funding.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
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