Phosphine imides

A list of more common silver complexing agents includes thiosulfates, thiocyanates, sulfites, cyanides, ammonia and other amines, thiols, thiourea, thioacids, thioethers and alkali halides. Most are not practical as fixing agents because they fail to satisfy all the above criteria. Many find use as silver halide stabilizers (Section 59.2.1.8). These include thiocyanate, thiourea and other thioorganic compounds. These and other complexing agents such as cyclic imides, phosphines and arsines find use in silver halide diffusion transfer processes (Section 59.2.1.6). 

The ligands that have been used in the preparation of metal nitride complexes are quite varied. They include halides, carbogenic groups (alkyl moiety and Cp ), pnic-togens (amine, amide, imide, phosphine, and arsine), and chalcogens (ether, alkox-ide, oxo, thioalkoxide, and selenides). Chart 1 provides a listing of the various ligands and the associated nitrido metal complexes. 

The efficient conversion of the furazans (70) into 1,4-dinitriles (71) is thought to occur via the nitrile oxides (72). Thermal decomposition of the diaziridones (73) in the presence of triethyl phosphite gives the phosphine-imine (75) and the isocyanate (74), which subsequently react together to give the carbodi-imide (76). ... 

Shobha et al. employed a novel sulfonated diamine containing a phosphine oxide moiety in the synthesis of a five—membered ring sulfonated poly-imide. The synthesis is shown in Figure 24. 

Trimerization of imidates is a valuable route to 1,3,5-triazines. Imidates can be considered as activated nitriles and cyclotrimerize more readily. Most symmetrical 2,4,6-trialkyl-1,3,5-triazines are easily formed, although large alkyl substituents may give rise to steric hindrance (61JOC2778). Symmetrical isocyanurates (525) are readily available from isocyanates, RNCO catalysts include tertiary amines, phosphines and sodium methoxide. Aldehydes RCHO and ammonia give hexahydro-1,3,5-triazines (526), known as aldehyde ammonias (73JOC3288). 

The complex formed in situ from bis(2-methylallyl)cycloocta-l,5-dienerutheni-um(II) [(COD)Ru[met]2l, a phosphine, and (TfO Sc has been found to catalyse efficiently the anti-Markovnikov addition of imides (RCO NH to terminal alkynes (g) R C CH to produce enimides R,CH=CHN(OCR)2. Depending on the phosphine employed, E- and Z-isomers can be accessed stereoselectively 96... 

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