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In chemistry a phosphine imide (sometimes abbreviated to phosphinimide) also known as a iminophosphorane is a functional group with the formula R 3 P=NR. While structurally related to phosphine oxide its chemistry has more in common with phosphonium ylides .
First phosphine imine-forming reaction is conducted involving treatment of the azide with the phosphine. The intermediate, e.g. triphenylphosphine phenylimide, is then subjected to hydrolysis to produce a phosphine oxide and an amine: R 3 P=NR' + H 2 O → R 3 P=O + R'NH 2. The overall conversion is a mild method of reducing an azide to an amine.
Mechanism of iminophosphorane formation. Aza-ylides can be obtained via the reaction of a tertiary phosphine and an organic azide with the loss of dinitrogen. Triphenylphosphine is a commonly used phosphine.
The Staudinger synthesis, also called the Staudinger ketene-imine cycloaddition, is a chemical synthesis in which an imine 1 reacts with a ketene 2 through a non-photochemical 2+2 cycloaddition to produce a β-lactam 3. [1] The reaction carries particular importance in the synthesis of β-lactam antibiotics. [2]
NPR 3 − is isoelectronic with phosphine oxides (OPR 3) and siloxides ([OSiR 3] −), but far more basic. [ 1 ] [ 2 ] By varying the R groups on P, a variety of ligands with different electronic and steric properties can be produced, and due to the high oxidation state of phosphorus, these ligands have good thermal stability. [ 3 ]
In recent years, several reagents such as Tris(2,2,2-trifluoroethyl)borate [B(OCH 2 CF 3) 3], [14] pyrrolidine [15] or titanium ethoxide [Ti(OEt) 4] [16] have been shown to catalyse imine formation. Rarer than primary amines is the use of ammonia to give a primary imine. [17] In the case of hexafluoroacetone, the hemiaminal intermediate can be ...
Chiral phosphine MBH catalysts often contain Bronsted acid moieties in their backbones. For example, chiral phosphines containing a Lewis base, a Bronsted acid, and an acid-activated Bronsted base were developed for an asymmetric aza-MBH reaction (86-96% yield, 79-92% ee). The Bronsted acid and base moieties were proposed to be involved in the ...
Phosphinoimidate complexes of transition metals containing the [R 3 P=N] − ligand are known to adopt several bonding modes. [1] [3] In complexes with metal ions in low oxidation states (+I, +II), the [R 3 P=N] − group often serves as a μ 3-N bridging ligand.