- Novel Di-isopropylamino Derivatives of Trivalent Phosphorus
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Reduction of (iPr2N)2PCl with LiAlH4 in diethyl ether gives (iPr2N)2PH; reaction of iPr2NPCl2 with Mg in boiling tetrahydrofuran gives either the cyclotetraphosphine (iPr2N)4P4 or the 1,2-dichlorobiphosphine iPr2NP(Cl)-P(Cl)NiPr2 depending upon the Mg:iPr2NPCl2 mole ratio.
- King, R. Bruce,Sadanani, Narayan D.,Sundaram, Ponnuswamy M.
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- SYNTHESE UND SPEKTROSKOPISCHE CHARAKTERISIERUNG VON CYCLOPENTADIENYLEISEN-KOMPLEXEN MIT P-N-LIGANDEN DES TYPS (C6H5)3-nP(NR2)N (n = 0-3; R = CH3, C2H5)
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The complex cations BF4 (L = (C6H5)3-nP(NR2)n; n = 0-3; R = CH3, C2H5) have been obtained from the reaction of BF4 (I) with L.The reaction of I with E(NR2)3 (E = As, Sb; R = CH3) is also described.Spectroscopic investigations (IR, 1H, 13C and 31P NMR) indicate an increase in electron density on the iron center through increase of the number of P-bound NR2 groups.
- Schumann, Hans
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- Cyclization of C-phosphorylated (PIII) arylformamidines to 3H-1,3-benzazaphospholes
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A synthesis of 3H-1,3-benzazaphospholes starting from C-phosphorylated P(III) arylformamidines has been developed. Electron-donating substituents were found to enhance markedly the rate of the cyclization, with substituents at the meta position having the greatest effect. A plausible mechanism of the cyclization was proposed based on DFT calculations.
- Marchenko, Anatolyi,Koidan, Heorgii,Hurieva, Anastasiya,Merkulov, Anatolyi,Pinchuk, Aleksandr,Yurchenko, Aleksandr,Rozhenko, Alexander B.,Jones, Peter G.,Th?nnessen, Holger,Kostyuk, Aleksandr
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experimental part
p. 7748 - 7758
(2011/10/17)
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- Dismutation of arylene phosphorodiamidites: Specific features and aspects of preparative use
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The dismutation of arylene phosphorodiamidites derived from the simplest phenols and naphthols and of their dibasic analogs was studied. The main regular trends of this process and the limits of its synthetic applicability were determined. Pleiades Publishing, Inc., 2006.
- Rasadkina,Slitikov,Nifant'ev
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p. 183 - 197
(2008/02/08)
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- Dismutation of diamidoarylphosphites
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Some examples of spontaneous dismutation of diamidoarylphosphites in different solvents were studied, and features of the process were revealed.
- Nifantyev, Edward E.,Rasadkina, Elena N.,Slitikov, Pavel V.,Vasyanina, Larisa K.
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p. 2465 - 2477
(2007/10/03)
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- Solid-phase chemical synthesis of phosphonoacetate and thiophosphonoacetate oligodeoxynucleotides
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Phosphonoacetate and thiophosphonoacetate oligodeoxynucleotides were prepared via a solid-phase synthesis strategy. Under Reformatsky reaction conditions, novel esterified acetic acid phosphinodiamidites were synthesized and condensed with appropriately protected 5′-O-(4, 4′-dimethoxytrityl)-2′-deoxynucleosides to yield 3′-O-phosphinoamidite reactive monomers. These synthons when activated with tetrazole were used with an automated DNA synthesizer to prepare phosphonoacetic acid modified internucleotide linkages on controlled pore glass. The phosphinoacetate coupling products were quantitatively oxidized at each step with (1S)-(+)-(10-camphorsulfonyl)oxaziridine or 3H-1,2-benzodithiol-3-one-1,1-dioxide to produce mixed sequence phosphonoacetate and thiophosphonoacetate oligodeoxynucleotides with an average per cycle coupling efficiency of greater than 97%. Completely deprotected, modified oligodeoxynucleotides were purified by reverse-phase HPLC and characterized by ion exchange HPLC, 31P NMR, and MALDI/TOF mass spectroscopy. Both analogues were stable toward hydrolysis with snake venom phosphodiesterase and stimulated RNase H1 activity.
- Dellinger, Douglas J.,Sheehan, David M.,Christensen, Nanna K.,Lindberg, James G.,Caruthers, Marvin H.
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p. 940 - 950
(2007/10/03)
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- Reactions of N,N′-dialkylcyclohexane-1,2-diimines with trivalent phosphorus acid chlorides
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N,N′-Dialkylcyclohexane-1,2-diimines react with trivalent phosphorus acid chlorides to give, depending on the structure of the organophosphorus reagent and reaction conditions, either 1,3,2-diazaphospholanes (three-coordinate phosphorus) containing the cy
- Lodochnikov,Gryaznova,Gryaznov,Musin,Kibardin
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p. 437 - 442
(2007/10/03)
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- Features of Chemical Behavior of Phosphenium Cations Stabilized by Two Intramolecular Donor-Acceptor N→P Bonds
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Properties of a new class of organophosphorus compounds, chelated phosphenium cations containing two intramolecular donor-acceptor N→P bonds, were studied. These cations react with nucleophiles with cleavage of the N→P bonds to give neutral products. On the contrary, in reactions with electrophiles the cationic structure and the N→P bonds are preserved. First representatives of five-coordinate cations containing a phosphazo group were prepared, and their structure was studied by single crystal X-ray diffraction.
- Pipko,Balitskii,Chernega,Sinitsa
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p. 530 - 535
(2007/10/03)
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- THIONO COMPOUNDS. 8. MUTAGENIC ACTIVITY OF REPRESENTATIVE AMIDES OF THIOPHOSPHORIC ACID
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Amides of thiophosphoric acid were studied, in order to initiate correlations of mutagenicity with structure, by use of a modified Ames assay.Representative thiophosphoramides of the structure (XArNH)3PS were not mutagenic, irrespective of whether X was a reference hydrogen atom, an electron-withdrawing, or an electron-donating group.One phosphoramidothioate of the structure (2,4-X2ArNH)P(S)(OCH2CH3)2 effected base-pair mutation when X was F (but not when X was CH3), when S-9 liver homogenate with exogenous NADP was used; when X was H, only inconsistent mutagenic activity following metabolic activation was observed even at concentrations near those that produced acute cellular toxicity.Mutagenicity of these N-arylamides thus appears to follow guidelines concluded for esters, (RO)3PS, i.e. that mutagenesis is most probable when two groups are small enough to permit nucleophilic attack by a biomacromolecule on the electrophilic phosphorus atom.That the third group should be electron withdrawing again seems important although it need not be a good leaving group.An alkyl thionamide, 3PS, resembled the oxygen counterpart, 3PO, to which it probably is biotransformed, in being only marginally mutagenic.We conclude that the hazard of mutagenesis is likely to be less with amides than with esters of thiophosphoric acid and that most of the representative thioamides tested are unlikely to pose serious mutagenic hazards. - Key Words: Ames assay, base-pair mutation, mutagenesis, phosphoramidothioate, thionamide, thiophosphoramide
- Mitchell, William M.,Breau, Alan P.,Swinson, Joel,Field, Lamar
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p. 151 - 158
(2007/10/02)
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- Tetrakis(dialkylamino)cyclotetraphosphines and Bis(dialkylamino)dihalobiphosphines
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Dehalogenation of R2NPCl2 (R = isopropyl or cyclohexyl) with magnesium in tetrahydrofuran gives the corresponding cyclotetraphosphines (R2N)4P4; the corresponding biphosphines (i-Pr2N)2P2X2 (X = Cl and Br) can be isolated from reactions of i-Pr2NPX2 with more limited quantities of magnesium.Dehalogenations with magnesium of R2NPCl2 derivatives having R2N groups smaller than diisopropylamino lead to redistribution of the dialkylamino groups giving (R2N)2P-P(NR2)2 (R2N = piperidino) or (R2N)3P (R2N = diethylamino or dimethylamino).Such redistribution reactions can be suppressed but not eliminated by using the homogenous dehalogenating agent (Me3Si)2Hg in hydrocarbon solvents.The steric bulk of the diisopropylamino groups in (i-Pr2N)4P4 reduces its chemical reactivity relative to other cyclotetraphosphines; thus (i-Pr2N)4P4 is unreactive toward oxygen, carbon disulfide, potassium metal, and various metal carbonyls under conditions where other cyclotetraphosphines react with these reagents.However, the P4 ring in (i-Pr2N)4P4 is cleaved under mild conditions by hydrogen chloride as well as by bromine and iodine.
- King, R. Bruce,Sadanani, Narayan D.
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p. 1719 - 1722
(2007/10/02)
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- Bis(dialkylamino)phosphines
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Reactions of LiAlH4 with sufficiently sterically hindered (R2N)2PCl derivatives (R = isopropyl and ethyl but not methyl) in diethylether give the corresponding (R2N)2PH derivatives as air-sensitive, vacuum-destillable liquids.Analogous reactions of LiAlH4 with sufficiently sterically hindered heterocycles (CH2)n(NR)2PCl (R = tert-butyl, n = 2 and 3; R not methyl, n not 2) give the corresponding heterocyclic PH derivatives (CH2)n(NR)2PH.The dialkylamino groups in (R2N)2PH undergo successive alcoholysis with the alcohols R'OH (R' = methyl, ethyl, isopropyl, andtert-butyl) to form (R2N)(R'O)PH and (R'O)2PH derivatives, which are identified by their phosphorus-31 NMR spectra.The derivatives (R2N)(R'O)PH (R = isopropyl; R'= methyl, ethyl, isopropyl, and tert-butyl) can be isolated by vacuum distillation as air-sensitive liquids, but the derivatives (R'O)2PH generally decompose upon attempted vacuum distillation.The (R2N)2PH derivatives undergo base-catalyzed addition to (R2N)2PCH=CH2 to give the corresponding diphosphines (R2N)2PCH2CH2P(NR2)2, provided that the R2N groups are not too bulky .The mass spectra and NMR spectra of the new organophosphorus compounds are described.
- King, R.B.,Sundaram, P.M.
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p. 1784 - 1789
(2007/10/02)
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- NEW DIALKYLAMINO DERIVATIVES OF TRIVALENT PHOSPHORUS
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Recent developments in the chemistry of (R2N)2PH, (R2N)(R'O)PH, (R2N)4P4, and R2NP(Cl)-P(Cl)NR2 derivatives are discussed.
- King, R. B.,Sadanani, N. D.,Sundaram, P. M.
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p. 125 - 128
(2007/10/02)
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