Hydrophosphination of acrylonitrile

Scheme 5-4 Platinum-catalyzed hydrophosphination of acrylonitrile using PH3 (Eq. I) and PH (CH2CH2CN)2 (Eq. 2). The proposed structure of a telomeric by-product of this reaction (I) Is also shown...

To avoid the complications posed by formation of dinuclear complexes, Glueck and coworkers studied the hydrophosphination of acrylonitrile using the Pt(0) catalysts Pt(diphos)(CH2CHCN) (diphos = dppe or dcpe. Scheme 5-7). 

Scheme 5-7 Pt(diphos)-catalyzed hydrophosphination of acrylonitrile with primary and secondary phosphines...

Recently, the chiral Pt(0) precatalyst Pt[(R, R)-Me-Duphos](trows-stilbene) (11) has been used to prepare enantiomerically enriched chiral phosphines via hydrophosphination of acrylonitrile, t-butyl acrylate and related substrates. This chemistry is summarized in Scheme 5-13. 

For example, this mechanism was proposed in Pt-catalyzed hydrophosphination of acrylonitrile and acrylates. P-H oxidative addition gave Pt-phosphido hydride... 

Table 6.1 Results of Pt-catalysed (Scheme 6.5). hydrophosphination of acrylonitrile...

Glueck s group has reported catalytic DKR processes in which secondary phosphines were converted into the corresponding enantio-enriched tertiary phosphines by platinum-catalysed asymmetric hydrophosphination of acrylonitrile, or by platinum-catalysed asymmetric alkylation of secondary phosphines. The key intermediates were diastereomeric phosphide complexes with chiral ancillary ligands (L -Pd PRR )- Their relative rates of P-inversion and phosphorus-carbon bond formation controlled the enantioselectivity of the product formation. As shown in Scheme 2.66, the reactions allowed moderate enantioselectivities of up to 71% ee and 77% ee, respectively, to be achieved. 

The reaction involves the formation of Ph2P(0)-PdL -0P(0)Ph2 (3) by the reaction of PdMe2L with Ph2P(0)H and Ph2P(0)0H, and the subsequent insertion of alkynes into the Ph2P(0)—Pd bond of 3. Some other related reports are known, which include the Pt-catalyzed hydrophosphination of acrylonitrile via carbon-carbon double bond insertion into a Pt—P bond. ... 

Scheme 5-9 Palladium-catalyzed hydrophosphination of acrylonitrile with a disecondary phosphine...

Pringle PG, Smith MB (1990) Platinum(0)-catalysed hydrophosphination of acrylonitrile. J Chem Soc Chem Commun 1701-1702... 

Pringle et al. have reported Pt-mediated hydrophosphination of acrylonitrile as the first example of transition-metal-catalyzed hydrophosphination of alkenes [111]. Tris(cyanoethyl)phosphine complex of Pt catalyzed addition of H-P(CH2CH2CN)2 with formation of the P(CH2CH2CN)3. The reaction in acetonitrile was carried out at RT. Kinetic measurements and NMR studies suggested two parallel reaction pathways including mononuclear and dinuclear Pt intermediates (Scheme 8.43) [111-113],... 

Later Glueck et al. have shown that Pt-catalyzed hydrophosphination of acrylonitrile took place via the catalytic cycle, which includes (1) oxidative addition of P-H bond to the metal (2) olefin insertion into the Pt-P bond and (3) reductive... 

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