6783-71-7Relevant academic research and scientific papers
Regioselectivity of the photochemical addition of ammonia, phosphine, and silane to olefinic and acetylenic nitriles
Guillemin, Jean-Claude,Breneman, Curt M.,Joseph, Jeffrey C.,Ferris, James P.
, p. 1074 - 1082 (2007/10/03)
An investigation of the regioselectivity and mechanisms of the photochemical addition of NH3, PH3, and SiH4 to olefinic and acetylenic nitriles is described. The photolysis of NH3 in the presence of acrylonitrile led to the α-addition product 2-aminopropanenitrile (2), propanenitrile, and 2,3-dimethylbutanedinitrile (3). When NH3 was photolyzed in the presence of substituted derivatives (crotononitrile, methacrylonitrile, or 1-cyclohexenecarbonitrile), the α-addition products were still obtained. However, under similar reaction conditions, only the β-addition products, 7 and 8, were obtained from acrylonitrile and PH3, or acrylonitrile and SiH4, respectively. On the other hand, the photolysis of 2-butynenitrile and NH3 gave the β-addition products, (Z)- and (E)-3-aminocrotononitrile (10). The photolysis of these acetylenic nitriles with PH3 or SiH4 also gave the β-adducts (12) and (13). The α-addition of NH3 proceeds by the stepwise addition of H· and ·NH2, respectively, to the α,β-unsaturated nitriles. The β-addition products are formed by a radical chain mechanism initiated by photochemically generated radicals. The radical chain pathway provides an explanation for a number of previously described photochemical additions to olefins and acetylenes. Photochemical processes similar to the addition of ammonia and phosphine to unsaturated organic compounds may have played a role in the evolution of the atmosphere of the primitive Earth, and may even be currently occurring in the atmospheres of other planets.
Dual Radical/Polar Pudovik Reaction: Application Field of New Activation Methods
Semenzin, Delphine,Etemad-Moghadam, Guita,Albouy, Dominique,Diallo, Ousmane,Koenig, Max
, p. 2414 - 2422 (2007/10/03)
The Pudovik reaction (addition of organophosphorus compounds containing a labile P-H bond with alkenes and alkynes) can progess via a radical or (and) ionic mechanism. A comparative and systematic study including various reagents and different activation methods (heating, photochemical or ultrasonic irradiation, and dry medium supported reactions) is presented. Photolysis is the most efficient method for the radical processes, but in a few examples, ultrasonic irradiation can be more appropriate since the reaction time is shorter and ultrasound did not induce side-reactions (in particular Z/E isomerization). Dry medium process on basic solid support is the best anionic activation (yield, time, selectivity, purification facilities). Ultrasound, by its mechanical effects, can contribute to increase yield compared to the classical thermal method under these basic conditions. All the activation methods are efficient whatever the unsaturated substrates for the phosphine reactivity, whereas the appropriate activation method is exclusively determined by the nature of the unsaturated system for the thiophosphine (or phosphine oxide) reactivity.
Self-replication of tris(cyanoethyl)phosphine catalysed by platinum group metal complexes
Costa, Emiliana,Pringle, Paul G.,Smith, Martin B.,Worboys, Kerry
, p. 4277 - 4282 (2007/10/03)
The platinum(0) complex [Pt(tcep)3], tcep = P(CH2CH2CN)3, catalyses the formation of tcep from PH3 and CH2=CHCN. The complexes [M(tcep)3] (M = Pt, Pd or Ni) and [MCl(tcep)3] (M = Rh or Ir) are compared for their catalysis of the reaction of PH(CH2CH2CN)2 with CH2=CHCN to give tcep and it is shown that the platinum(0) complex is the most efficient. The platinum(0) catalysis has been studied in detail, monitoring the kinetics by 31P-{1H} NMR spectroscopy. It is revealed that the kinetics are a complex function of the concentration of product tcep. Qualitatively, the rates also depend on [CH2=CHCN] and [catalyst]. Both 31P-{1H} and 195Pt-{1H} NMR spectroscopy suggests that addition of CH2=CHCN to [Pt(tcep)3] gives the complex [Pt(tcep)2(η2-CH2=CHCN)] which undergoes phosphine exchange on the NMR time-scale. The binuclear complex [Pt2H2(tcep)2{η-P(CH2CH 2CN)2}2], formed upon addition of PH(CH2CH2CN)2 to trans-[PtHCl(tcep)2] in the presence of base, is shown to be a catalyst precursor for the reaction of PH(CH2CH2CN)2 with CH2=CHCN. Two parallel mechanisms involving mononuclear and binuclear intermediates are discussed to rationalise these observations.
Platinum(0)-catalysed Hydrophosphination of Acrylonitrile
Pringle, Paul G.,Smith, Martin B.
, p. 1701 - 1702 (2007/10/02)
The tris(cyanoethyl)phosphine complex 3> catalyses the addition of PH3 or PH(CH2CH2CN)2 to CH2=CHCN to give P(CH2CH2CN)3.
