By means of phosphines

Buffered diazonium salts can be used to quaternize tertiary phosphines with an additional aryl group.351 

Quaternary salts of Mannich bases are useful for the preparation of quaternary phosphonium salts containing heterocyclic substituents, which are inaccessible or difficultly accessible by other routes 352,353. 

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Analogously to the phosphorylation of alcohols with phosphoric azolides the phos-phinylation is carried out by means of phosphinic azolides (CH2CI2/C2H5OC2H5). In the following case a I2/C2H5OC2H5) protonated diphenylphosphinic imidazolide is used to give the allylic diphenylphosphinic esters in good yields ... 

Using a split-and-pool combinatorial synthesis strategy, Tamanoi and coworkers developed a library of approximately 4000 heterocycles generated from resin-bound allenoates by means of phosphine catalysis [36,37]. This library was initially screened to identify GGTase I inhibitors (Table 8.1), and some potent GGTase I inhibitors with novel... 

Replacement of metals by phosphorus by means of phosphines and phosphonium salts... 

The isomerization of an allylic amine to an enamine by means of a formal 1,3-hydrogen shift constitutes a relatively small structural change. However, this transformation could be extremely valuable if it could be rendered stereoselective. In important early studies, Otsuka and Tani showed that a chiral cobalt catalyst, prepared in situ from a Co(ii) salt, a chiral phosphine, and diisobutylaluminum hydride (Dibal-H), can bring about the conversion of certain pro-chiral olefins to chiral, isomeric olefins by double bond migra-... 

C. C. Stephenson and W. F. Giauque. "A Test of the Third Law of Thermodynamics by Means of Two Crystalline Forms of Phosphine. The Heat Capacity. Heat of Vaporization and Vapor Pressure of Phosphine. Entropy of the Gas". J. Chem. Phys.. 5. 149-158 (1937). 

Examples of the intermolecular C-P bond formation by means of radical phosphonation and phosphination have been achieved by reaction of aryl halides with trialkyl phosphites and chlorodiphenylphosphine, respectively, in the presence of (TMSlsSiH under standard radical conditions. The phosphonation reaction (Reaction 71) worked well either under UV irradiation at room temperature or in refluxing toluene. The radical phosphina-tion (Reaction 72) required pyridine in boiling benzene for 20 h. Phosphinated products were handled as phosphine sulfides. Scheme 15 shows the reaction mechanism for the phosphination procedure that involves in situ formation of tetraphenylbiphosphine. This approach has also been extended to the phosphination of alkyl halides and sequential radical cyclization/phosphination reaction. ... 

Figure 19 explains what in principle happens the cluster monolayer on the dendrimer film is mobilized by means of CH2CI2 vapour (a b). The phosphines are then removed by the SH functions (b->c). The bare AU55 nanoclusters move between the dendrimer molecules to form crystals (Auss) which finally appear on the surface (c d). The formation of crystalline superlattices of naked AU55 particles proves their stability which is founded in their perfect cuboctahedral shape. The (Auss) species is a novel modification of the element gold. 

A highly thermostable palladium-phosphine oxazoline catalytic system, shown in Eq. (11.37), has recently been reported to yield high ee under single-mode micro-wave irradiation [54, 55]. The use of this P,N-ligand catalytic system resulted in even higher ee than the P,P-ligand BINAP [56], The reactions were performed in acetonitrile (b.p. 81-82 °C) and superheating increased the temperatures up to 145 °C, as measured by means of a fluoroptic probe. 

In the case of the bis phosphine derivatives of the group 7b metals, the lability of the oxygen atoms was so markedly retarded by substitution that it was necessary to enhance their reactivity by means of base catalysis (15, 14), a process having mechanistic features common wi Tx general base catalysis of the hydration of ketones (eq. 6) (15). 

One of the very first attempts to hydrogenate aromatic compounds by means of a single-site metal catalyst was reported by Fish and coworkers, who were able to tether RhCl(PPh3)2 moieties to a cross-linked phosphinated styrene/divinylbenzene (DVB) resin (RhCl(PPh3)2/P) (Fig. 16.3). 

Alternatively, phosphine imines 266 were treated with various phenylacetyl chlorides 270 (method B). Surprisingly, phosphonium salts 271 were isolated with 25 to 97% yield, which could be deprotonated by means of a base to build up the corresponding phosphoranes 272 (66-89% yield). Upon heating to... 

By means of a kinetic investigation of the reaction between diborane and phosphine at 0 °C in the gas phase, Brumberger and Marcus were able to describe the probable course of the reaction using the following equations ... 

The asymmetric fluorination of enolates by means of chiral metal complexes has been reported with Selectfluor in the presence of a chiral Lewis acid derived from TADDOL (TiCl2/TADDOL), or with F-A-sulfonimide (NFSI) with palladium complexes and chiral phosphines. 

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