Principal properties amines

Carlson, R., Prochazka, M.P. and Lundstedt, T. Principal Properties for Synthetic Screening Amines. Acta Chem. Scand., 1988, B42, 157-165. 

Steric environment of the amine nitrogen atom The descriptors used to determine the principal properties of amines do not take steric effects into account. It is therefore suggested that steric factors should be considered as a separate additional criterion when test items are selected. 

Fig. 15.22 Principal properties of amines, (a) Score plot (b) Loading plot.

It has for long been assumed that morpholine is the preferred amine in this reaction, and that other amines generally give inferior results. With the aim of examining the scope of the reaction with regard to amine variation, the reaction was run with a series of amines selected by their principal properties. Acetophenone was used as the ketone substrate in these reactions, and quinoline was used as a solvent. The reason for using quinoline was that it permits a large span of the reaction temperature (b.p 237 ° C). 

If it is assumed that the structure of the substrates can be described by the nature of the substituents, it would be possible to use common substituent parameters as descriptors of the substrates. Several studies on substituent parameters by principal components analyses have now been published.[ll] When the experiment described here were carried out, one such study was available.[lla] This study described the variation of the properties of aromatic substituents by a two-component model, and this model was used for the selection of the substrates in the present study. The principal properties of amines and solvents are also described by two-component models. Each axis in the reaction space is therfore two-dimensional, and the whole reaction space is six-dimensional. To span the whole reaction space by selecting test systems from each "comer" would require 2 = 64 different test systems. It would be... 

A number of other N-substituted 2-pyrroHdinones have been offered commercially or promoted as developmental products. These materials offer different and sometimes unique solvency properties. AH are prepared by reaction of butyrolactone with suitable primary amines. Principal examples are Hsted in Table 4. 

The final class of water-soluble synthetic detergents derived from petroleum are the cationics. These products, when ionized, have the hydrophobic portion of the molecule in the cation. They are of interest principally because of the bactericidal properties they exhibit. Their performance as detergents is poor. The principal products marketed to date have been derived from normal long-chain amines, but procedures for their preparation from petroleum hydrocarbons (1) have been described as follows ... 

A set of 126 primary, secondary, and tertiary amines characterized by seven property descriptors afforded two significant principal components which described 85% of the total variance. For details, see [63]. A preliminary study of 29 amines was used for the selection of co-substrates in studies on the Willgerodt-Kindler reaction [21]. 

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