Phosphines amino-functionalized

When an aminophosphonium species is used with an aryl lithium reagent, cleavage of the amino functionality from phosphorus is observed, producing the parent phosphine.10 This reaction has been used to prepare stable phosphoranes from aminophosphonium species using dilithium reagents (Figure 5.6).10 It should be noted that the... 

Metalation of amino-functionalized tertiary phosphine 388 with BuLi in THF afforded quantitatively [160] the rearranged product 391 (Scheme 126). Both intermediate lithium derivatives 389 and 390 form stoichiometric complexes with THF. No product of methylene group insertion into the C-P bond in 389 was detected. 

It has been mentioned already that the PN bonds of halogeno-substituted amino-phosphines undergo less shortening than SiN bonds in the corresponding silamines. However, the effect of amino function is much more pronounced in the case of the former compounds and results in a greater elongation of PCI than of SiCl bonds. 

It will be recalled that substituted amino functions are displaced more slowly from phosphorus than halogen at low temperatures. An interesting case in the series of phosphinous halides involves the synthesis of phosphorus heterocycles having ultraviolet spectra that suggest aromatic character (46). Addition of Grignard reagents to the phos-... 

The synthesis of functionalized phosphinic and phosphonic acids and their derivatives. Part B diazo, nitro and amino functionalized acids... 

Related reactions of thiolate anions with ort/zo-chloromethyl-phenyl(diphenyl)phosphine have provided a range of ort/ o-alkyl and aryl-thiomethylphenyl(diphenyl)phosphines. " The reactions of 2-amino-alkylphosphines with isocyanates and isothiocyanates have provided routes to new chiral phosphinoalkyl-urea and -thiourea ligands. Similarly, treatment of hydroxy- or amino-functional arylphosphines with isocyanides in the presence of a cyclooctadienepalladium(II) complex results in the formation of bidentate arylphosphino-carbene palladium complexes. New chiral phosphinoarylphosphoramidite ligands, e.g.,... 

The novel synthesis of unsymmetrical dialkylphosphinic acids (573) under mild conditions has been performed by Lecouvey and co-workers.This synthesis started from the hypophosphoric acid (570) which reacted with triethyl orthoformate to give the //-phosphinate (571). The letter underwent base-promoted alkylation to give (572). For the formation of the second P-C bond in the phosphinate (573), a one-pot procedure involving reaction of (572) has been applied (Scheme 139). This methodology was extended to the synthesis of dialkylphosphinic acids with amino functionality. 

The synthesis of phosphinate derivatives 32 described by Pompei was performed by coupling of the key macrocyclic acid 30 [35, 39], with racemic phosphinic acid 31 (Scheme 5) [34], This coupling occurred by converting the carboxylic acid of pyroUdine ring with ethyl chloroformate into an anhydride intermediate which was subsequently trapped by the amino function of phosphinic acid derivatives. 

Following the general trend of this account, monodentate phosphinous amide ligands and bidentate AT-phosphino phosphinous amides or bis(amino-phosphanes) are included in the following discussion, but not other bidentate ligands bearing additional, different phosphorus functionalities, as for instance phosphinous amide-phosphane bidentate ligands. 

Amino groups of functionally substituted phosphines easily undergo nucleophilic substitution. Mutual transitions were shown to exist for the aminomethyl derivatives of phenylphosphine (80IZV1438), acyclic compounds being transformed into cyclic ones with variation in the size of the rings [Eq. (45)]. 

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