- ALKYLATION OF ACYCLIC AND CYCLIC DIAMINES AND POLYAMINES
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Alkylation of diamines and polyamines by allyl and methallyl chlorides or by chloropropenes has been used to obtain polyalkylpolyamines that had not been described previously.The alkylation of the polyamines by allyl and methallyl chlorides proceeds more energetically in comparison with the alkylation by ethyl chloride or chloropropenes.The alkylation of either cyclic and acyclic polyamines begins with the primary amino group.With increasing length of the chain and the alkyl radical at the nitrogen of the alkylated polyamines, their capability for reacting with the evolved hydrogen chloride drops off, and this leads to a decrease in yield of the desired products owing to the loss of activity of the original or partly alkylated polyamines.
- Zagudullin, R. N.,Baimetov, Z. M.
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p. 889 - 894
(2007/10/02)
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- Transalkylation Reaction. Homogeneous Catalytic Formation of C-N Bonds
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We have performed kinetic and mechanistic studies on homogeneous ruthenium-catalyzed transalkylation of tertiary amines.From these studies we have derived a kinetic expression for transalkylation catalysis based on initial reaction rates.We find that transalkylation proceeds most efficiently in alcoholic solvents (e.g., MeOH or EtOH), under a slight pressure of CO, with a mixed-metal, iron-ruthenium catalyst.The mechanism appears to be in one which a metal cluster of at least two and most probably three atoms binds the amine through insertion into an α C-H bond to give a metallazacyclopropane or metal-iminium complex.Nucleophilic attack by free amine on the complex, or an immediate derivative, follows, and subsequent rearrangement of the intermediate formed gives transalkylation products.The catalyst system has been tested as a synthetic tool for the oligomerization and cyclization of tertiary diamines.These preliminary studies have been quite succesful.Thus, N,N,N',N'-tetramethylethylenediamine can be transformed into Me3N and N,N'-dimethylpiperazine with good conversion and high selectivity.N,N,N',N'-Tetraethylethylenediamine can be transformed into Et3N and the linear, perethyl, ethylenediamine dimer, trimer, tetramer, and pentamer with excellent conversion.
- Wilson, Robert B.,Laine, Richard M.
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p. 361 - 369
(2007/10/02)
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