Amino phosphino

Figure 44 Structures of heterocyclic amino-, phosphino- and arsinogallanes 622, 626, and 627.

Vacuum thermolysis (160°C) of the hemiaminal 11 generates the azaphos-phetane 65 in 85% yield.32 This product clearly results from the intramolecular insertion of the transient (amino) (phosphino)carbene 2h into the C-H bond of a diisopropylamino group bonded to phosphorus. Note that the four-membered heterocycle 65 is formed exclusively in spite of the ratio of six methyl-CH bonds to one methine-CH bond, and that only one of the two possible diastereomers is detected. The same regio- and diastereo-selectivity have already been observed with the di(phosphino)carbene 2g,74 but is in marked contrast to the exclusive formation of five-membered rings... 

The amino(phosphino)carbene 12a with a pyramidalized phosphino substituent behaves as a,p-bidentate ligand to give highly stable Rh(I) [53] and Pd(II) [54] complexes. 

Several unique synthetic strategies for bidentate(amino)(oxy)- and (amino)(aryl) carbenes have been described (Scheme 10). For the former, the reaction of the amino(phosphino)carbene with an ort/io-quinone leads to the transient formation of a zwitterionic species featuring both a phosphonio nucleofuge and an aryloxide nucleophile that allow for a subsequent intramolecular substitution process. The... 

It is interesting to note that in the reaction of (188) with [TcOCU] , the 0x0 group is replaced by a doubly deprotonated amino group. The mixed imido-amido Tc complex [Tc(app)Cl2(Happ)j (263) was synthesized and structurally characterized with Re. Neutral, mixed amino-phosphino ligands can stabilize the soft [Tc=N] + core in the expected way, whereas the harder [Tc=0] + core imposes subsequent acid/base reactions. Stabilization is then mainly achieved by deprotonation, in order to compensate for the relatively high charge. ... 

The stereospecificity observed with (Z)- and ( )-2-deuteriostyrene presents convincing evidence for the concerted nature of the cyclopropanation reaction, and therefore the genuine singlet carbene nature of stable (phosphino)(silyl)carbenes (I). The diastereoselectivity is at first glance surprising. Indeed, it is clear that steric factors cannot govern the observed selectivity since the bis(amino)phosphino group... 

Interestingly, highly regioselective reactions were also observed by addition of Lewis acids to the (amino)(phosphino)carbene (XVd). Indeed with one equivalent of BF3 OEt2 the quantitative formation of the carbene-BF3 complex was observed, whereas the softer Lewis acid BH3 interacts selectively with the phosphorus lone pair to afford a new stable carbene XVId (Scheme 8.25). ... 

Figure 8.17. Molecular structure of the (amino)(phosphino)carbene rhodium complex XVdRH.

A Rh—P Experimental and theoretical studies of complexes based on (amino)(phosphino)carbenes 2004JOM1431, 2003CEJ5858, 2002JA11834... 

A M-P M = Ni, Pd Complexes based on (amino)phosphino)carbenes 2005JOM5541... 

Baceiredo and Bertrand combined the two privileged coordination moieties to an (amino)(phosphino)carbene ligand [117], after which the palladium complex formed by reaction of this ligand and PdCl2(cod) was isolated and structurally characterized. Whilst the results of the amination experiments were not... 

However, substitution of the second phosphine has never been observed and, under stoichiometric reaction conditions the substitution equilibrium is strongly shifted toward bis-phosphine complexes. Under catalytic reaction conditions, where an excess of amine is present, a substantial amount of amino(phosphino) palladium(ll) complex is present in solution. Under these circumstances, a substitution of an amine, rather than of a phosphine, by the alkyne is of greater importance. The details of a comprehensive mechanistic study on these interactions were reported recently for the coupling of Phi and a terminal alkyne mediated by [PdL2], with L = PPh3 or AsPh3, in the presence of secondary amines (Scheme 6.35) [103]. 

Valine Amino phosphino ferrocene [5] Helicene BINOL... 

Direct complexation of an (amino)(phosphino)carbene 296 and an (amino)(oxy)carbene 297 featuring a phosphino group in position-6 to the carbene with [RhCl(CO)2]2 provided two new Rh(l) carbene complexes, 298 and 299. ... 

Liu C-Y, Cheng M-C, Peng S-M et al (1994) Coordination of an amino-phosphino macrocycle with ( -cyclopentadienyl)- and ( / -pentamethylcyclopentadienyl)-iron complexes. J Organomet Chem 468 199-203... 

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