Phosphino-amine ligands

Phosphino)amines, ligands containing one, two or three P—N bonds, have attracted much interest due to their ease of preparation, their diverse coordination chemistry, and their catalytic applications. There are several synthetic routes now available, as highlighted below. 

In a similar way, the same authors also reported new half-sandwich t -Cp -rhodium(ra) and r -Cp -ruthenium(ii) complexes 31-34 (Scheme 8), from the corresponding bis(phosphino)amine ligands, thiophene-2-(A ,Af-bis(diphenylphosphino)methylamine) 31 and 32 or furfutyl-2-(N,N-bis(diphenylphosphino)amine) 33 and 34. The structures of the new complexes were elucidated by spectroscopic techniques and successfully applied to transfer hydrogenation of various ketones in the presence of 2-propanol as the hydrogen source. 

The bis(phosphino)amines are versatile ligands and an extensive coordination chemistry, based on variable coordination patterns (Scheme 30), has been developed on this basis... 

One particularly interesting reaction of coordinated (phosphino)amines is their ability to undergo orthometallation, as observed for ligands (198) and (199) at platinum(ll) and rhodium(III) metal centers.444 These constitute the first examples of CH activation of a (phosphino)amine, in... 

Bulky electron rich phosphino-amines as ligands for the Suzuki coupling reaction of aryl chlorides... 

BULKY ELECTRON RICH PHOSPHINO-AMINES AS LIGANDS FOR THE SUZUKI COUPLING REACTION OF ARYL CHLORIDES... 

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... 

With ligands containing phosphorus With phosphino amines CU (C6H5)2P(0)CH2CH2N H(CH3)2 C13 ) room 1613c. 1.98 Farad distorted tetrahedral coordination hydrogen bonded chains 74N9... 

Historically, McGuinness and Wasserscheid first reported on the preparation of bis (phosphino)amine chromium(III) chloride complexes, which, upon activation with MAO, act as highly selective catalysts for the production of 1-hexene from ethylene [156]. Bis(sulfanyl)amine-type ligands were subsequently found to be less expensive and easier to prepare [157]. These systems were then optimized by researchers at Sasol Technology and patented as selective catalysts for the formation of 1-hexene (>97%) using a low amount of MAO (30-100 equiv.) [158]. 

X-ray structures) copper precatalysts have been isolated from ////-bis(diphenyl-phosphino)amme ligands and CuCl. Wan and co-workers [144, 145], proposed a system with the ability to couple aryl or heteroaiyl iodides with a bountiful variety of alkyl amines (Scheme 9). For these reactions, the authors also used a phosphoms ligand (phosphoramidite L23) with CuBr in DMF. 

Helmchen and coworkers employed a,co-amino-1,3-dienes as substrates [51]. By using palladium complexes with chiral phosphino-oxazolines L as catalysts, an enantiomeric excess of up to 80 % was achieved. In a typical experiment, a suspension of Pd(OAc)2, the chiral ligand L, the aminodiene 6/1-90 and an aryltriflate in dimethylformamide (DMF) was heated at 100 °C for 10 days. Via the chiral palladium complex 6/1-91, the resulting cyclic amine derivative 6/1-92 was obtained in 47% yield and 80% ee (Scheme 6/1.23). Using aryliodides the reaction time is shorter, and the yield higher (61 %), but the enantiomeric excess is lower (67% ee). With BINAP as a chiral ligand for the Pd°-catalyzed transformation of 6/1-90 and aryliodide, an ee-value of only 12% was obtained. 

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