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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 117 (1995), S. 11027-11028 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
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  • 2
    ISSN: 0044-2313
    Keywords: Triphenylmethyl Phosphorus Compounds ; Phosphorus Fluorine Compounds ; Co-ordination Compounds ; Crystal Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organophosphorus Compounds with Tertiary Alkyl Substituents. V Synthesis and Reactions of triphenylmethyl-substituted Dihalophosphines TrtPX2 (Trt = Triphenylmethyl-, X = F, Cl, Br); X-Ray-Crystal Structures of Triphenylmethyl dichlorophosphine TrtPCl2 and Triphenylmethylthiophosphonic Difluoride TrtP(:S)F2The dihalophosphines TrtPX2 (X = Cl: 2, Br: 3) were obtained in the reaction of TrtP(:O)(H)OH 1 with PCl3 and PBr3, respectively. 2 could also be synthesized from TrtMgCl and PCl3, 3 from 2/Me3SiBr. TrtPF2 4 was prepared by the fluorination of 2 with NaF or from TrtLi/PF2Cl. The reduction of 2 with LiAlH4 or HSiCl3/NaOH(aq) yielded TrtPH2 6, the reaction with NaF/H2O led to TrtP(:O)(H)F 9. (TrtPCl2)2Mo(CO)4 10 was observed in the system 2/(NOR)Mo(CO)4 by 31P-NMR-spektroscopy. 4 was oxidized with TrtN3 or sulfur to give the λ4P(V)-compounds TrtP(:NTrt)F2 11 and TrtP(:S)F2 12 respectively. Whereas the oxidation of 4 and tBuPF2 with tetrachloro-o-benzoquinone (TOB) led to the corresponding difluorophosphoranes 13 and 14, no reaction could be observed when 4 was treated with hexafluoroacetone (HFA) at elevated temperatures. In a fashion typical of difluorophosphines, 4 reacted with (COD)MCl2 (M = Pd, Pt) or (NOR)Mo(CO)4 to give the co-ordination compounds 15, 16 and 18 a. Upon heating cis-(TrtPF2)2Mo(CO)4 18 a isomerized to give the thermodynamically favoured trans-complex 18 b. The reaction of 4 with Fe3(CO)12 led to (TrtPF2)Fe(CO)4 17 as the only phosphorus-containing product, instead of the phosphinidene complex TrtP(μ-F)2Fe3(CO)9. X-ray structure analyses of compounds 2 and 12 were carried out. The P—C bond in 2 is unusually long (193.3 pm). The F—P—F angle in 12 is narrow (98.14°).
    Notes: Die Dihalogenphosphine TrtPX2 (Trt = Ph3C; X = Cl: 2, Br: 3) sind durch Umsetzung von TrtP(:O)(H)OH 1 mit PCl3 bzw. PBr3 zugänglich. 2 ist auch durch Grignardierung von PCl3 mit TrtMgCl, 3 aus 2/Me3SiBr darstellbar. TrtPF2 4 wurde durch Umsetzung von 2 mit NaF oder aus TrtLi und PF2Cl erhalten. Aus 2 und LiAlH4 oder HSiCl3/NaOH(aq) war das primäre Phosphin TrtPH2 6 zugänglich, die gleichzeitige Einwirkung von NaF und H2O auf 2 führte zu TrtP(:O)(H)F 9. Im System 2/(NOR)Mo(CO)4 (NOR = Norbornadien) wurde als Produkt (TrtPCl2)2Mo(CO)4 10 31P-NMR-spektroskopisch nachgewiesen. TrtPF2 4 ließ sich mit TrtN3 bzw. Schwefel zu den λ4P(V)-Verbindungen TrtP(:NTrt)F2 11 bzw. TrtP(:S)F2 12 umsetzen. Während die Oxidation sowohl von TrtPF2 4 als auch von tBuPF2 mit Tetrachlor-o-benzochinon (TOB) zu den Difluorphosphoranen 13 und 14 führte, war bei der Einwirkung von Hexafluoraceton (HFA) auf 4 auch bei erhöhter Temperatur keinerlei Umsetzung festzustellen. In für Difluorphosphine typischer Weise bildete 4 mit (COD)MCl2 (COD = Cyclooctadien; M = Pd, Pt) bzw. (NOR)Mo(CO)4 unter Verdrängung des olefinischen Liganden die Komplexe 15, 16 und 18 a. cis-(TrtPF2)2Mo(CO)4 18 a konnte durch Erhitzen in den thermodynamisch bevorzugten trans-Komplex 18 b umgewandelt werden. Die Reaktion von 4 mit Fe3(CO)12 führte nicht zu einem Phosphinidenkomplex des Typs TrtP(μ-F)2Fe3(CO)9; stattdessen wurde (TrtPF2)Fe(CO)4 17 als einziges phosphorhaltiges Produkt isoliert. Von den Verbindungen 2 und 12 wurden Röntgenstrukturanalysen durchgeführt. Die P—C-Bindung in 2 ist mit 193,3 pm ungewöhnlich lang. In 12 ist der F—P—F-Winkel gestaucht (98,14°).
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  • 3
    ISSN: 1042-7163
    Keywords: Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The addition of dimethylphosphine oxide and its trimethylsiloxyphosphorus(III) derivative, generated in situ, to 3-thiazolines was found to yield dimethyl 4-thiazolidinylphosphine oxides via three different synthetic routes. The structures of two products were confirmed by X-ray analysis; common features include approximate envelope conformations of the five-membered rings and hydrogen bonding of the form N-H· · ·O=P. © 1997 John Wiley & Sons, Inc. Heteroatom Chem 8: 207-215, 1997.
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  • 4
    ISSN: 0947-3440
    Keywords: Carbenes ; Ylides ; Thiazol-2-ylidene ; Dimerizations ; Carbene dimer ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis, characterization and X-ray crystallographic structure determination are described for a stable thiazol-2-ylidene 2. This thiazol-2-ylidene is the first example of a stable, crystalline carbene in which the singlet carbene center bears a sulfur substituent. The carbene 2 is the closest stable analog of the important thiamin (vitamin B1) carbene. Although the thiazol-2-ylidene 2 is sufficiently stable to isolate at room temperature in the absence of moisture and oxygen, it will dimerize to form a normal carbene-carbene dimer {2}2. With the isolation and structure determination of both 2 and {22}, this system is the first in which a stable carbene and its corresponding dimer have been isolated and characterized. Additionally reported is the “reduced” 2H-thiazoline 2 · H2 in which the former carbene center in 2 has been reduced to a methylene (CH2) group. Thiazol-2-ylidenes with smaller groups on nitrogen (e.g. mesityl or methyl) are too unstable to allow easy isolation. The dimer from 3,4,5-trimethylthiazol-2-ylidene possesses a very unusual geometry in which one of the former carbene centers is planar while the second is pyramidal.
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  • 5
    ISSN: 0044-2313
    Keywords: Staudinger Reaction ; Phosphazides ; Phosphorus-Fluorine Compounds ; NMR ; X-Ray Crystal Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Tris(dimethylamino)phosphine, Triisopropylphosphine and tButyldifluorophosphine with Tertiary Alkyl Azides: Phosphazide Formation versus Phosphinimide Formation. X-Ray Crystal Structures of triphenylmethylazide and Tris(dimethylamino)-N-triphenylmethyl PhosphazideTris(dimethylamino)-phosphine and triisopropylphosphine react with tertiary alkyl azides RN3 (R = tBu, 1-Ad, Trt) to give the corresponding phosphazides 1a-1c and 2a-2c, which involve a linear PN3R-unit. The coordination geometries of the N3 chains in triphenylmethylazide and 1c are completely different, associated with a change of hybridisation. Hence, the N3-group of the triphenylmethylazide is nearly linear, whereas that of 1c shows approximately tetrahedral angles. The coordination geometry at the central nitrogen atom also depends on the substituents, possibly because of their varying ability to delocalize the π-electron system. In contrast, the reaction of tbutyldifluorophosphine with the same azides RN3 led to the tbutyldifluorophosphinimides 3a-3c of the type tBuP(:NR)F2. The hydrolysis of these compounds afforded the tbutylphosphonamidic fluorides tBuP(:O)(NHR)F (R = 1-Ad: 4b, Trt: 4c), instead of the expected substitution products tBuP(:NR)(OH)F.
    Notes: Tris(dimethylamino)phosphin und Triisopropylphosphin reagieren mit tertiären Alkylaziden RN3 (R = tBu, 1-Ad, Trt) zu den entsprechenden Phosphaziden 1a-1c und 2a-2c, die eine PN3R-Kette besitzen. Die Koordinationsgeometrien der N3-Ketten in Triphenylmethylazid und in 1c sind, bedingt durch eine Änderung der Hybridisierung, völlig verschieden. So ist die N3-Gruppierung im Triphenylmethylazid nahezu linear, während bei jener in 1c annähernd Tetraederwinkel gefunden werden. Die Geometrie am zentralen Stickstoffatom hängt auch von der Natur der Substituenten ab, möglicherweise wegen deren unterschiedlicher Fähigkeit zur Delokalisierung des π-Elektronensystems. Im Gegensatz zu Obigem führt die Reaktion von tButyldifluorphosphin mit den gleichen Aziden RN3 zu den tButyldifluorphosphin mit den gleichen Aziden RN3 zu den tButyldifluorphosphinimiden tBuP(:NR)F2 3a-3c. Die Hydrolyse dieser Verbindungen ergibt die tButylphosphonsäureamidfluoride tBuP(:O)(NHR)F (R = 1-Ad: 4b; Trt: 4c) anstatt der erwarteten Substitutionsprodukte tBuP(:NR)(OH)F.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 173-176 
    ISSN: 0044-2313
    Keywords: Cyclopolyphosphines ; NMR ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tris-1-adamantylcyclotriphosphine and Tetrakis-1-adamantylcyclotetraphosphine: Two Peradamantylated Examples from the Cyclopolyphosphine Series (RP)nDepending on the halogen substitution at the phosphorus atom, 1-adamantyldihalophosphines of the type 1-AdPX2 (X = Cl, Br) react with sodium to give tris-1-adamantylcyclotriphosphine 1 (X = Cl) or tetra-kis-1-adamantylcyclotetraphosphine 2 (X = Br). The latter is also formed in the reaction of approximately equimolar quantities of 1-adamantylphosphine and phosgene. The 31P-NMR-parameters are discussed and compared with those of the analogous tbutyl compounds.
    Notes: In Abhängigkeit von der Halogensubstitution am Phosphoratom reagieren 1-adamantylsubstituierte Dihalogenphosphine des Typs 1-AdPX2 (X = Cl, Br) mit Natrium zu Tris-1-adamantylcyclotriphosphin 1 für X = Cl oder Tetra-kis-1-adamantylcyclotetraphosphin 2 für X = Br. Letzteres läßt sich auch durch Umsetzung annähernd äquimolarer Mengen 1-Adamantylphosphin und Phosgen darstellen. Die ermittelten 31P-NMR-Parameter werden diskutiert und denen strukturanaloger tButyl-Verbindungen gegenübergestellt.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 898-907 
    ISSN: 0044-2313
    Keywords: Primary phosphine ; Primary phosphine oxide, sulfide selenide ; H/D-Exchange ; NMR ; 1-Adamantyldichlorophosphine ; Co-ordination compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Reactions of Primary Phosphines Involving Sterically Demanding Substituents: The Case of 1-AdamantylphosphineThe reaction of 1-AdPH2 1 with equimolar amounts of H2O2 · C(:O)(NH2)2, sulfur and selenium furnished the corresponding primary phosphine oxides, sulfides and selenides, 2, 5 and 7. In these compounds the PH-protons may be exchanged quantitatively for deuterons by the action of CH3OD/trifluoroacetic acid anhydride, while the reaction of 1 with the same agent gave a mixture of 1-AdPH2 1, 1-AdPHD 1a and 1-AdPD2 1b. The reaction of 1 with activated carbonyl compounds, R1R2C(:O) led to the di-adducts 9 and 10 and to the mono-adduct 11 of the general type 1-AdPH2-n[C(OH)R1R2]n [n = 2 for 9 (R1 = H, R2 = CCl3) and 10 (R1 = H, R2 = COOH); n = 1 for 11 (R1 = Ph, R2 = CF3)]. 11 decomposed in solution, giving 1-AdPH2 1 and trifluoroacetophenone. 1-Adamantylphospholanium tribromide 12 was synthesized by heating 1 in 1,4-dibromobutane and was converted into the corresponding hexafluorophosphate 12a and the oxide 13. The action of a 2.5-fold excess of phosgene on 1 gave 1-AdPCl2 15 in high yield. The reaction of 1-AdPH2 1 with Ph3SnCl led to the formation of P—Sn-bonds. An attempt at the separation of the mixture of the mono- and distannylation products, 16 and 17, was unsuccessful. Metal complexes of the type cis-(1-AdPH2)2MCl2 (M = Pd: 18, M = Pt: 19) were obtained by reaction of 1-AdPH2 1 with (COD)MCl2 (COD = 1,5-cyclo-octadiene). In the same way (NOR)Mo(CO)4 (NOR = norbornadiene) and (CHT)Mo(CO)3 (CHT = cycloheptatriene) reacted with two or three equivalents of 1 to give the expected co-ordination compounds, cis-L2Mo(CO)4 21 and fac-L3Mo(CO)3 22 (L = 1), respectively. The phosphido complex Cp(CO)2Mo(μ-1-AdPH)(μ-H)Mo(CO)2Cp 23 (Cp = cyclopentadienyl) was formed by refluxing a solution of 1 and [CpMo(CO)3]2 in methylcyclohexane.
    Notes: Die Umsetzung von 1-AdPH2 1 mit äquimolaren Mengen H2O2 · C(:O)(NH2)2, Schwefel und Selen führte zu den entsprechenden primären Phosphinoxiden, -sulfiden und -seleniden 2, 5 und 7. In ihnen ließen sich die PH-Protonen durch Einwirkung von CH3OD/TFA-Anhydrid quantitativ gegen Deuteronen austauschen, während die Einwirkung dieses Agens auf 1 zu einem Gemisch aus 1-AdPH2 1, 1-AdPHD 1a und 1-AdPD2 1b führte. Die Umsetzung von 1 mit aktivierten Carbonylverbindungen R1R2C(:O) lieferte im Fall von R1 = H, R2 = CCl3 oder COOH die Diadditionsprodukte 9 und 10, im Fall von R1 = Ph, R2 = CF3 das Monoadditionsprodukt 11 vom allgemeinen Typ 1-AdPH2-n[C(OH)R1R2]n mit n = 2 bei 9, 10 und n = 1 bei 11, wobei sich 11 in Lösung unter Rückbildung der Edukte zersetzte. 1-Adamantylphospholaniumtribromid 12 wurde durch Erhitzen von 1 in 1,4-Dibrombutan gebildet und in das Hexafluorphosphat 12a und das Oxid 13 umgewandelt. Die Einwirkung eines 2,5fachen Überschusses Phosgen auf 1 lieferte 1-AdPCl2 15 in hoher Ausbeute. Die Reaktion von 1 mit Ph3SnCl führte zur Knüpfung von P—Sn-Bindungen, das Gemisch der Mono- und Distannylierungsprodukte 16 und 17 ließ sich jedoch nicht trennen. Metallkomplexe des Typs cis-(1-AdPH2)2MCl2 (M = Pd: 18, M = Pt: 19) wurden aus 1-AdPH2 und (COD)MCl2 dargestellt (COD = 1,5-Cyclooctadien). Ebenso reagierten (NOR)Mo(CO)4 (NOR = Norbornadien) und (CHT)Mo(CO)3 (CHT = Cycloheptatrien) mit zwei bzw. drei Äquivalenten 1-AdPH2 1 unter Bildung der erwarteten Komplexe cis-L2Mo(CO)4 21 und fac-L3Mo(CO)3 22 (L = 1). Der Phosphidokomplex Cp(CO)2Mo(μ-1-AdPH)(μ-H)Mo(CO)2Cp 23 (Cp = Cyclopentadienyl) wurde durch Umsetzung von 1 mit [CpMo(CO)3]2 in siedendem Methylcyclohexan erhalten.
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  • 8
    ISSN: 0044-2313
    Keywords: N′,N′,N″,N″-Tetramethylguanidine ; (N-(N′,N′,N″,N″-tetramethyl)guanidinyl)substituted Phosphoryl compounds ; Phosphorylamides ; BF3 Adduct of Phosphorylamides ; X-Ray Crystal Structure Analysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Structure, and some Reactions of N-(N′,N′,N″,N″-tetramethyl)guanidinyl-substituted Phosphoryl CompoundsThe tetramethylguanidinyl-substituted phosphoryl compounds 1-10 were prepared in the reaction of the appropriate chlorophosphoryl compounds with either N′,N′,N″,N″-tetramethylguanidine (HTMG) or N-trimethylsilyl-(N′,N′,N″,N″-tetramethyl)guanidine (TMSTMG). With methyl iodide 1 reacted with N-alkylation to give the ammonium salt 11. 1 reacted with BF3 · Et2O at both imino nitrogen atoms with formation of the bis-BF3-adduct 12. The X-ray structure determination of phenylphosphonic acid-bis(N′,N′,N″,N″-tetramethylguanidinide) 3 shows shortened PN-bonds and widened PNC-angles, consistent with the partial double bond character of the PN-bond.
    Notes: Die tetramethylguanidinylsubstituierten Phosphorylverbindungen 1-10 wurden durch Umsetzung der entsprechenden Phosphinsäure- und Phosphonsäure-Chloride mit N′,N′,N″,N″-Tetramethylguanidin (HTMG) oder N-Trimethylsilyl-N′,N′,N″,N″-tetramethylguanidin (TMSTMG) dargestellt. Mit Methyliodid reagierte 1 unter einfacher N-Alkylierung zur Ammoniumverbindung 11. Mit BF3 · Et2O reagierte 1 and beiden Iminostickstoffatomen unter Bildung des Bis-BF3-Adduktes 12. Das Phenylphosphonsäure-bis(N′,N′,N″,N″-tetramethyl-guanidinid) 3 wurde einer Einkristall-Röntgenstrukturanalyse unterzogen. Es wurden leicht verkürzte PN-Bindungen und aufgeweitete PNC-Winkel beobachtet. Dies deutet auf partiellen Doppelbindungscharakter der PN-Bindung hin.
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  • 9
    Publication Date: 1997-12-01
    Print ISSN: 0002-7863
    Electronic ISSN: 1520-5126
    Topics: Chemistry and Pharmacology
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  • 10
    Publication Date: 1995-11-01
    Print ISSN: 0002-7863
    Electronic ISSN: 1520-5126
    Topics: Chemistry and Pharmacology
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