Temperature isolate, effect

Aromatic ketones react even more slowly than aliphatic ketones and require strong acid catalysts and higher temperatures to effect the isolation of good yields of imine. Acetophenone reacts with aniline at reflux temperature in the presence of aniline hydrochloride to give the imine [9] (see Table VIII). 

The hb-PAEs of hb-P13 and hb-P15 contain NLO-active azo-functionalities, which are soluble, film-forming, and morphologically stable (Tg > 180 °C). Their poled films exhibited high SHG coefficients ( 33 up to 177pm/V), thanks to the chromophore-separation and site-isolation effects of the hyperbranched structures of the polymers in the three-dimensional space (Table 5) [28]. The optical nonlinearities of the poled films of the polymers are thermally stable with no drop in d33 observable when heated to 152 °C (Fig. 8), due to the facile cross-linking of the multiple acetylenic triple bonds in the hb-PAEs at moderate temperatures (e.g., 88 °C). 

The asymmetric allylboration of representative aldehydes with either 9R or 9S was examined in EE (3h, -78 °C). In all cases, the homoallylic alcohols 10 were obtained in i96% ee. These results are summarized in Table 2. The intermediates 11 were isolated in excellent yields in essentially pure form after solvent removal. For the reactions of 9R, solutions (-0.5 M) of SR and (IS, 25)- (+)- pseudoephedrine (1.0 equiv) in MeCN were heated at reflux temperature to effect the transesterification with crystalline (+)-8 being isolable by simple filtration. An analogous procedure was used for the 95 reactions employing (-)-pseudoephedrine to... 

The thermal resistances and time constants for a number of different sample holders are shown in Figure 5.20. The resistance values obtained in C and D were not very reproducible due to the positioning of the heater in the sample area. The time-constant values, however, were much less affected. It is well known that the heat sensitivity of an isolated container-type holder decreases with increasing temperature. This effect, which is due to the increase in thermal conductivity, k, results in a reduced value for the thermal resistance. 

For two of the lanthanoid M ions, equations (68) and (69) do not hold. They are Eu, and Sm, / ( if2 /,)> where another state lies fairly close above the ground state which then cannot be considered in isolation. For the Fq state, / = 0 and fEu and /u,ed are predicted to be zero. In fact, xeu 100 mm mor independent of temperature. This effect arises because the Fi state, a few hundred cm higher, interacts with the ground state to give substantial second-order Zeeman effect terms in equations (64) and (65) and, as there is no first-order term and the higher... 

If we apply pressure to an incompressible body in the course of an adiabatic process, the body may unexpectedly expand. The increase of pressure leaves even an incompressible body literally not cool. The body can accept energy and can warm up when thermally isolated. Since the pressure has no effect on the dimensions, but the temperature has effect, the body may expand on heating. 

They used different catalysts for the synthesis of the desired product such as p-toluenesulfonic acid (/>-TSA), CF3SO3H, and solid-supported catalyst such as NaHS03-Si02, but these were found to be less effective. The desired product was isolated only in 25-30% yield and the use of iodine increased the product yield significantly. The reaction was carried out using 0.1 mmol of iodine. The yield of the product was decreased when 0.05 mmol of iodine was used or suppressed when the reaction was performed at room temperature. The effect of solvents, e.g., DMF or tetrahydrofuran (THF) was also examined and found to be counterproductive. 

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