Novel Betaines of the Hexaalkylguanidinio-carboxylate Type
2009 ◽
Vol 64
(11-12)
◽
pp. 1617-1624
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Betaines 7a, b and 8a, b have been prepared from 3- and 4-piperidinecarboxylic acid and N,N,N',N'-tetraalkyl-chloroformamidinium chlorides via the corresponding methyl esters. These betaines are highly hygroscopic, thermally very stable, and, with the exception of 7b, have rather low melting points. They undergo a surprisingly facile alkaline cleavage of the hexaalkylguanidinium moiety. They react with dichloromethane by a twofold nucleophilic substitution to form methylene dicarboxylates such as 11. TheNMR (1H, 13C) data of betaines 7 and 8 are discussed
1993 ◽
Vol 51
◽
pp. 132-133
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1966 ◽
Vol 16
(01/02)
◽
pp. 018-031
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Keyword(s):
Keyword(s):
2018 ◽
Keyword(s):
2019 ◽
2019 ◽
Vol 56
(4)
◽
pp. 279-286
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