Mesityl azide

Cycloaddition Reactions with Mesityl Azide, Diphenyldiazomethane, Isocyanides, and Benzonitrile... 

Surprisingly, in contrast to the reaction of the Si=P bond with mesityl azide, the reaction of 15a with diphenyldiazomethane resulted in the formation of the [2+l]-cycloadduct 35 (Scheme S).38 The bonding situation in 35 (Fig. 11) may be described in terms of a 7r-complex, by employing the Dewar-Chatt-Duncanson model, in which the Si=P bond acts as v donor and acceptor at the same time (Scheme 9). The corresponding [2+31-cycloaddition product 36 was generated only on thermal activation of 35. 

A 5-phosphonio-substituted 1,2,3,4-triazaphosphole (121) results from a dichlorophos-phinomethyl-phosphonium salt, an excess of DABCO and mesityl azide. The 2-phosphonio-l-... 

Ultraviolet irradiation of mesityl azide 288 in the presence of tetracyanoethylene has resulted in the isolation of the intermediate azomethine ylide 289 (from trapping of the aryl nitrene) together with its rearrangement product, the spiroazepine 290 (Scheme 36) <1997JOC3055>. Photolysis (at 313 nm) at low temperature of 1- and 2-azido-naphthalenes in an Ar matrix provided access to the novel seven-membered cyclic ketenimines 291 and 292, respectively <2004JA237>. 

Although Cp Rh=NR compounds have not been isolated from reactions of [Cp RhCl2]2 with LiNHR an indication that Cp Rh=N(2,6-Pr2C6H3) exists for a short time at 0°C is the trapping reaction with mesityl azide, mesN3, which gives the A,A -diaryl tetrazine complex by a 1,3-dipolar cycloaddition 111... 

Another approach utilized the reaction of tosyl azide with aryl Grignard reagents and fragmentation of the resulting tosyltriazene salts by aquv ous sodium pyrophosphate. Mesityl azide (124) was thus obtained from mesityl bromide in 63% yield... 

The diarylstannylene (16-3) reacts with mesityl azide to give the distannaaziridine (16-4), which in solution is in equilibrium with the stannaimine (16-5) and stannylene, and this mixture reacts with further azide to give the distannaazetidine (16-6).24... 

Mesitylmagnesium bromide prepared from mesityl bromide in dry ether added dropwise to an ice-cooled ethereal soln. of tosyl azide, stirring continued 0.5 hr., the resulting dry crude triazene salt suspended in dry ether, ice-cooled, aq. Na-pyrophosphate added dropwise at 0-20° to sequester the magnesium, and stirred overnight -> mesityl azide. Y ... 

Parallel to the work of Bergman et al., Cummins et al. published a closely related system obtained from a vanadium(in) precursor and mesityl azide leading to a vanadium(V) diazenylimido complex, which loses dinitrogen already at room temperature. Interestingly, the loss of dinitrogen from the vanadium(V)diazenylimido complex follows second-order kinetics and crossover was found in a double labelling experiment, which is in contrast to the observations of Bergman et al. with tantalum complexes. 

Reactions of [Cp Ir(NR)] R = Bu 662a or 2,6-Pr 2C6H3 662b with 2,6-xylyl isocyanide [(Xyl)NG], mesityl isocyanate, and mesityl azide were studied by Danopoulos et The bridged dimers [Cp"lt(/r-NCsFl9)]2... 

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