Dimethyl- -diphenyl

Aus 1-Methyl-2,4,5-triphenyl- bzw. 1,2-Dimethyl-4,5-diphenyl-imidazol und Acetonitril werden beim Belichten ebenfalls [2 4- 2]-Cycloadditionsprodukte erhalten1250 1251. Dagegen findet mit 1-unsubstituierten Imidazolen wie z.B. 2-Phenyl- und 2,4,5-Triphenyl-imidazol unter Iso-merisierung zu 2H-Imidazolen cine Additon in 2-Stellung statt1250 12S1. 

Cyclohexyl dibeiizyl II566. l Pnenyl 3-. phen lby].cycIohexan 5 1316. 1.2-Dimethyl-4.5-diphenyl-OTclohexan 3,654. 

Table 10. Characteristics of aminopropyl-terminated poly(dimethyl-diphenyl)siloxane oligomers 66 171)...

The effect of structural variations in siloxane oligomers in the synthesis and properties of the resulting siloxane-urea copolymers have also been investigated 161). In these studies aminopropyl-terminated poly(dimethyl-diphenyl)siloxane and poly-... 

Dimethyr diphenyl sulphone 4,4 -Dimethyl" diphenyl sulphone... 

Analysis of the products of the photolysis of Zr (benzyl) 4 in toluene at 30°C in the region 300-450-nm with mass spectrometry shows that the predominant peak is due to p-benzyl toluene with small amounts of dibenzyl, and 4,4 -dimethyl diphenyl. Rate measurements (Fig. 5a) suggest that in this region of the spectrum the polymerization proceeds through radical intermediates (29). This concept is supported by the fact that the spectrum of zirconium tetrabenzyl has a maximum at 317 nm and is identical with that found for the benzyl radical using flash photolysis techniques (30). Also zirconium tetrabenzyl on irradiation in toluene solution produces... 

Dimethyl diphenyl sulfone 4,4 -dicarboxylate, s29 Dimethyleneimine, el48 Dimethylene oxide, el46... 

The enantiomeric excesses of the phosphonic acid was measured using 31P NMR after treatment with (IS, 2S)-(—)-N,N -dimethyl(diphenyl-ethylene)-diamine in CDCI3 and a catalytic amount of CD3OD. 

The square-planar geometry (with slight tetrahedral distortion) of these derivatives can be proved by that of the related Rh(I) complex with 2,2/-bis [o-(diphenylphosphine)benzylidene]amine -6,6/-dimethyl-diphenyl, [Rh(PPNN)]+, Figure 23.26... 

Synthesis of q,oi-Amlnopropyl Terminated Poly(dimethyl-diphenyl)-slloxane Oligomers... 

In this study our aim was to systematically synthesize a, oraminopropyl terminated (dimethyl-diphenyl)siloxane oligomers having low molecular weights (1000-3000 g/mole) and to subsequently analyze the composition and thermal behavior of the copolymers. 

Table II provides a summary of the results on the characteristics of aminopropyl terminated poly(dimethyl-diphenyl)-siloxane oligomers synthesized. These reactions were conducted in bulk at 160°C with K0H as the initiator. As can be seen from Table II the stoichiometric number average molecular weights sought and obtained are in very good agreement. The level of diphenylsiloxane incorporation was determined by UV spectroscopy. There is no absorption of dimethylsiloxane backbone in the spectral range of 240 to 280 nm. On the other hand, phenyl groups absorb very strongly over these wavelengths (Figure 3). For quantitative analysis we have used the absorption peak at 270 nm as the reference.

Figure 3. Typical UV absorption spectrum of D " or D "/D blend or a poly(dimethyl-diphenyl)siloxane oligomer (CHCl solution)...

Guanidine nitrate 28.0% Ammonium chromate 8.0% Dimethyl diphenyl urea 4.0% Beech charcoal 4.0%... 

N,N -Dimethyl-N -bis [phenyl]-ureo N,N -Dimethyl-carbarn Iide or N,N -Dimethyl-diphenyl-urea. See Centralite 2 in Vol 2, pp C137ff... 

Dimethyl-diphenyl-sulfide. See Di(tolyl)-sulfide in this Vol... 

Di(tolyl) -disulfides or Dimethyl-diphenyl-disulfide and Derivatives... 

T etranitro-S -dimethyl-diphenyl-disulfide or Bis(4,6-Dinitro-m-tolyl) ... 

Fig. 6. Tan 8 as a function of temperature for epoxy modified with 10 wt.-% of dimethyl/diphenyl siloxane oligomers...

Hexonltro-3,3 -dimethyl-dlphenylamine or Bis(3-methyl-2,4,6-tri-nitro-phenyl)-amine, [CHJ.C4H(NOJ)3]2NH, bm tables (from ale), mp 60°. Can be prepd by warming 4,6-dinitro-3,3 -dimethyl-diphenyl amine with nitric acid(d 1.5) on a water bath. Its expl props were not investigated... 

Treatment of the o-methyl diphenyl ether complex 58a with isobutyronitrile carbanion at —78 °C and then allowing the reaction mixture to warm up to room temperature affords the ipso complex 59a almost quantitatively. Ipso SNAr of the phenoxy group also occurs with acetonitrile, propionitrile, and alkoxycarbonyl carbanions (Scheme 28) [46]. Similarly, addition of isobutyronitrile carbanion to 2,3-dimethyl diphenyl ether complex 58b gives exclusively complex 59b under the same experimental conditions. 

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