- An improved synthesis of N-isocyanoiminotriphenylphosphorane and its use in the preparation of diazoketones
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An improved synthesis of N-isocyanoiminotriphenylphosphorane is reported. This reagent is a safe, stable, solid alternative to diazomethane and TMS-diazomethane in the Arndt-Eistert synthesis of diazoketones.
- Bio, Matthew M.,Javadi, Gary,Song, Zhiguo Jake
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- One-pot three-component reaction for the synthesis of novel series of fully substituted 1,3,4-oxadiazole derivatives bearing pyridine moiety
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(N-isocyanimino)triphenylphosphorane, 2-pyridinecarbaldehyde, and aromatic carboxylic acids (benzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, 3-methoxybenzoic acid, 1-naphthoic acid, and 2- naphthoic acid) undergo a 1:1:1 addition reaction underm
- Souldozi, Ali,Karami, Samad
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- Silver-Catalyzed Cascade Reaction of N-Isocyaniminotriphenylphosphorane with Aldehydes: Synthesis of Unsymmetrical Azines
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A direct synthesis of azines from the silver catalyzed domino interaction of N-isocyaniminotriphenylphosphorane and aldehydes is reported. The reaction proceeds through a tandem aza-Wittig, insertion, intramolecular cyclization and ring-opening processes.
- Wang, Yeming,Yu, Yang,Zhao, Liping,Ning, Yongquan
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- Silver-promoted regio- and stereoselective aminocyanation of alkynes for the synthesis of β-aminoacrylonitriles using N-isocyanoiminotriphenylphosphorane
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The silver-promoted intermolecular aminocyanation of alkynes for the synthesis of (Z)-β-aminoacrylonitriles is reported, using N-isocyanoiminotriphenylphosphorane (NIITP) as both the nitrile and amine source. The transformation proceeds in moderate to good yields, and in a regio- and stereoselective manner, using a wide range of acetylenes.
- Chen, Lingnan,Cao, Shanshan,Zhang, Jingping,Wang, Zikun
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supporting information
p. 1678 - 1681
(2019/05/29)
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- Four-component synthesis of disubstituted 1,3,4-oxadiazoles from N-isocyaniminotriphenylphosphorane, phenylacetylenecarboxylic acid, chloroacetone derivatives, and primary amines
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The 1:1 imine intermediate generated by the addition of primary amine to chloroacetone derivatives is trapped by N-isocyaniminotriphenylphosphorane in the presence of phenylacetylenecarboxylic acid, leading to the formation of the corresponding iminophosp
- Ramazani, Ali,Nasrabadi, Fatemeh Zeinali,Karimi, Zahra,Rouhani, Morteza
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p. 1818 - 1830
(2013/05/21)
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- Free and metal-coordinated (N-isocyanimino)triphenylphosphorane: X-ray structures and selected reactions
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An improved procedure for the synthesis of (N-isocyanimino)- triphenylphosphorane, C≡N-N=PPh3 (3), is described. The X-ray structure analysis reveals an unusually small N-N=P angle [115.2(2)°] and an N-N bond order of only about 1.5, which indicates considerable C≡N-N --P+ participation and electronically more-isolated functional groups (CN, P=N) in the isocyanide than, for example, in the isomeric N≡C-N=PPh3 (4) [C-N=P = 123.0(4)°, C-N bond order = 2.0]. In order to gain insight into the stereochemical consequences of metal coordination of 3, an X-ray structural study of [Cr-(CO)5C≡N-N= PPh3] (5) was also undertaken. Surprisingly, the central bond lengths (C-N, N-N) and angles (C-N-N) remain practically unchanged with noticeable coordination effects occurring only at the periphery of 5, with the N-N-P angle [112.3(2)°] further decreased by 15σ, the elongated (by 7σ) P-N bond, the somewhat shortened (by 4σ) P-C(Ph) bonds and even shorter C-H(Ph) bonds on the one side, and the well-known Cr-C(O)trans contraction on the other. Treatment of 5 or its tungsten derivative with anhydrous Bronstedt and Lewis acids such as CF3COOH, HCl, COS, phosgene or, most efficiently, [PdCl2(1,5-COD)] causes CN→NC isomerisation to give [M(CO)5N≡C-N=PPh3] [M = Cr (6), W (7)]. In solution, [PdCl2(CNNPh3)2] and Ph3BCNNPPh3 (8) slowly isomerize even without additional acid to give both free and Pd-coordinated 4 and Ph3BNCNPPh 3 (9), respectively. In the presence of catalytic amounts of [PdCl2(1,5-COD)], 3 is converted into 4 and the dimer Ph 3PN-C(CN)=N-NPPh3 (10) in an almost 1:1 ratio. The optimised geometries of the methyl derivatives of 3 and 4, namely Me 3P=N-N≡C (3c) and Me3P=N-C≡N (4c), are in excellent agreement with the experimental data; major differences between the isomers (P-N-N angle, N-N bond length) are explained by the higher electronegativity of the isocyano group as compared to the CN substituent, which, in turn, is a better π-acceptor). The reaction path of the isomerisation of 3 to 4 (3c to 4c) has also been studied computationally and been found to proceed via an [(P)=NA-N≡CA(N A-CA)] cyclic transition state. The overall process is exothermic by 50 kcal mol-1. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
- Stolzenberg, Heribert,Weinberger, Bernd,Fehlhammer, Wolf Peter,Puehlhofer, Frank G.,Weiss, Robert
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p. 4263 - 4271
(2007/10/03)
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- Reactions of bis(trimethylsilyl)isocyanamide and its isomers with chlorotriphenylphosphonium chloride: evidence for a transient dizomethylenetriphenylphosphorane. Crystal structure of NN->2
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Triphenylphosphine dichloride reacts with (Me3Si)2C=NN, Me3SiN=C=NSiMe3, and metal-coordinated CN-N(SiMe3)2 to give the iminophosphoranes CN-NPPh3, NC-NPPh3, and W(CO)5CN-NPPh3, respectively, and with free bis(trimethylsilyl)isocyanamine to give a dicatio
- Zinner, Gerhard,Beck, Gerhard,Fehlhammer, Wolf P.,Wiberg, Nils
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- Metal Complexes of Functional Isocyanides, VIII: (Isocyanoimino)triphenylphosphorane Metal Complexes
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The thermally unusually stable N-isocyanide CNNPPh3 (1) is prepared by the reaction of formylhydrazine with triphenylphosphane, tetrachloromethane, and triethylamine and reacted with metal compounds to give the complexes M(CO)5CNNPPh3 (M = Cr, Mo, W) (3-5), cis-Cr(CO)4(CNNPPh3)2 (6), Mn(η-C5H5)(CO)2CNNPPh3 (7), PF6 (8), PdX2(CNNPPh3)2 (X = Cl, I) (9a,b), cis-BF4 (11), and trans-2 (12).
- Weinberger, Bernd,Fehlhammer, Wolf Peter
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