Addition of nitrogen compounds

Kinetic dependences of the conversion of h-BN into c-BN in the Li-B-N-F system have been studied by introducing about 6% additional nitrogen with addition of nitrogen compounds [170]. The stoichiometry of the c-BN was increased by adding nitrogen (synthesis pressure 4.3 GPa, 1750-1850 K). 

There are many examples of transition catalyzed addition of nitrogen compounds to alkenes, alkynes,and so on. Secondary amines can be added to certain nonactivated alkenes if paUadium(II) complexes are used as catalysts. ... 

Addition of nitrogen compounds to carbonyl compounds usually leads to further reaction involving loss of water and formation of a C-N double bond. Since the end result is replacement of oxygen by nitrogen, these reactions are treated in subsection III of section 6.2 of this Chapter (see pages 504 et seq.). 

Although the addition of nitrogen compounds to the C=N bond of isocyanates offers a number of synthetic possibilities (see page 406), formal replacement of the isocyanate-oxygen by nitrogen has only recently become important and then only for one case. This case is the conversion of isocyanates into carbodiimides ... 

Grape and apple juices usually contain all of the trace nutrients required by Saccharomjces for fermentation of sugars to alcohol. Other fmit and diluted honey, as well as barley malt and rice extract, frequendy need additions of nitrogen, phosphoms, and potassium compounds, together with some autolyzed yeast to faciUtate the yeast growth necessary for fermentation. Stimulation oiy4.cetobacter frequendy requires the addition of autolyzed... 

Certain proteases, for example alkaline protease from Bacillus suhtilis, have also proven to be good catalysts for the Michael addition of nitrogen nucleophiles to a,/3-efhylenic compounds [118, 119]. 

As the adhesive factory will consume a large amount of methanol in its processes, the addition of this compound to carry out nitrogen removal would have a low cost, and is one of the most feasible options. 

As synthetic steps, the Michael additions of nitrogen nucleophiles were followed by nucleophilic substitutions of the chlorine atom with a primary amine and, finally, alkylations of the then secondary amino group with various alkyl bromides were performed just as previously developed for the chloro ester 1-Me in solution (see, e.g. Schemes 25,27,36 etc.). With differently substituted pyra-zoles as Michael addends, different primary amines and alkyl bromides, combinatorial libraries consisting of 8, 24 and 84 compounds were thus successfully prepared in ca. 60% yield and proved by the LC-MS technique to contain all the individual compounds in about equal amounts (Scheme 80) [127]. 

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