Nitrogen atmospheric utilization

The DSC thermogram (14) for cyclandelate (Wyeth-Ayerst Reference Standard No. 1361 is presented as Figure 6. The thermogram was obtained at a heating rate of 10 C/minute in a nitrogen atmosphere utilizing a Perkin-Elmer DSC-2. The thermogram exhibits no endotherms or exotherms other than that associated with the melt. 

All materials analyzed were ground to 40 mesh particle size, the standard amount of powder (0.1 g) was poured into the metal cuvette (1" diameter) and carefully spread to a uniform thickness. The cuvettes were placed in the separate test cells of the chemiluminescence apparatus, and covered by glass covers at room temperature under nitrogen atmosphere. Two different procedures have been utilized ... 

A further check of the quality of Equation 16.7 is provided in Table 16.3. The Td i/2 values of several commercial polymers, whose Yd /2 values could not be calculated by using the group contributions that were available when this work was done because of the lack of some of the needed group contributions, were estimated by utilizing Equation 16.7 to calculate Yd y2- The predicted values of Td j/2 were then compared with the results of dynamic TGA scans [28] obtained in an inert (nitrogen) atmosphere at a rate of lOK/minute on a DuPont TGA module. 

A new method for nitrogen fixation involved the treatment of titanium tetraisopropoxide with lithium metal and trimethylsilyl chloride in the presence of a nitrogen atmosphere to give either a titanium-nitrogen complex and/or N(TMS)3 9 (proposed structures) <04BCJ1655>. This reagent was utilized to prepare pyrrole, indoles, and other nitrogen heterocycles. For example, treatment of preformed 9 with enol triflate 8 led to fused pyrrole 10. 

Reagents. Diallyl fumarate was obtained from Pfaltz Bauer and was used without further purification. The impure diallyl maleate (failed in hydrosilylation), trichlorosilane, and trimethylorthoformate were obtained from Aldrich. Distilled DAM was obtained from Bimax Corp. and was utilized without additional treatment. Platinum catalysts and solvents were obtained internally from GE Silicones. All reactions were run under a nitrogen atmosphere. 

The cylindrical dumbbells were prepared by utilizing a CSI Mini-max injection molder equipped with a dry nitrogen atmospheric chamber at temperatures ranging from 220°C to 260°C with a residence time of 3 minutes. 

Mediation of 1,4-Conjugate Additions. The high lability of the formyl group under basic and acidic conditions makes it difficult to cleanly generate enolates or enols. In order to arrest the pronounced reactivity under the said conditions, the formyl group is usually transformed into a stable synthon. Trimethylsilyldiethylamine can be utilized to solve such problems. A novel protocol for direct 1,4-addition of naked aldehydes to electron-deficient double bonds employs a catalytic amount of trimethylsilyldiethyl-amine. For example, addition of but-3-en-2-one to a stirred solution of decanal and 0.5 equiv of trimethylsilyldiethylamine under nitrogen atmosphere yields the keto aldehyde in 67% yield (eq 24). The same conditions convert benzaldehyde and ethyl vinyl ketone into 2-benzyT5-oxoheptanal in 68% yield (eq 25). 

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