Methylation of p-tert-butylcalix[8]arene with MeI in the presence of strong bases (NaH, BaO/Ba- (OH)2, or Cs2CO3) in THF has been investigated. Composition of the reaction mixtures differs remarkably from those obtained using weak bases and described in a preceding paper. Several previously unreported methylated products [two dimethoxy- (21,5 and 21,4), a trimethoxy- (31,2,5), a tetramethoxy- (41,2,3,6), two pentamethoxy- (51,2,3 and 51,2,4), and three hexamethoxy- (61,2, 61,3, and 61,4)] have been isolated. In many cases the substitution pattern was assigned unambiguously on the basis of spectroscopic evidence only, while in others chemical correlation with known compounds was required.
Methylation of p-tert-butylcalix[8]arene. Products obtained in the presence of strong bases
F Cunsolo;
1998
Abstract
Methylation of p-tert-butylcalix[8]arene with MeI in the presence of strong bases (NaH, BaO/Ba- (OH)2, or Cs2CO3) in THF has been investigated. Composition of the reaction mixtures differs remarkably from those obtained using weak bases and described in a preceding paper. Several previously unreported methylated products [two dimethoxy- (21,5 and 21,4), a trimethoxy- (31,2,5), a tetramethoxy- (41,2,3,6), two pentamethoxy- (51,2,3 and 51,2,4), and three hexamethoxy- (61,2, 61,3, and 61,4)] have been isolated. In many cases the substitution pattern was assigned unambiguously on the basis of spectroscopic evidence only, while in others chemical correlation with known compounds was required.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
