Acylamines, cyclic

N,N-Dialkylalkanamides Cyclic N-Alkylamides Cyclic N-Acylamines Cyclic N-Acylaminoethers N,N-Dialkylimidazolidinone derivatives N-Alkylalkanamides Cyclic amides Alkanamides Nitrocompounds Nitroalkanes Nitroarenes Nitrobenzene Thlazole derivatives 1,3-Thiazole Sulfonamides... 

The INAS reaction of to-vinyl amides proceeds as shown in Eq. 9.42 to afford cyclopropylamine derivatives [77]. The reaction with cyclic imides derived from ovinylamines, furnishing acylaminal derivatives, was also found to proceed smoothly (Eq. 9.43) [78]. 

Resin-bound diols, amino alcohols, and dithiols, which reversibly form cyclic acetals with aldehydes and ketones, have been successfully used as linkers for carbonyl compounds (Entries 5-11, Table 3.40). Acetal formation on insoluble supports can be achieved by azeotropic removal of water (C6H6, TsOH, reflux [720]), whereas dithio-acetals can be prepared by acid-catalysis alone (BF3 OEt2 or TMSC1 CHCI3,0 °C, 2 h [721]). /V-Acylaminals such as R-CFI(OMe)NFI-CO-Pol have been prepared by treatment of resin-bound amides H2NCO-Pol with aldehydes in the presence of HC(OMe)3 and TFA [722],... 

Conversion of an amine into a substituted amide is a convenient and widely used method for the protection of amino groups. Monoacylation of a primary amine often affords sufficient protection, i.e., against oxidation, alkylation, etc., and more complete protection is obtained by forming cyclic diacyl derivatives. Acyclic diacylamines easily revert to mono-acylamines and have only been used under very mild conditions [20]. Of the simple acylamines in common use the stability increases in the order formyl < acetyl < benzoyl and many more complex acyl groups have been evaluated in order to adjust the stability of the derivatives for various purposes. 

In connection with studies on the thermolysis of oxazolin-5-ones, the 2-arylthio-substituted derivative (49) has been observed to undergo thermally induced cycloelimination of carbon dioxide to give the 2H-1,3-benzothiazine (52), presumably via the ylide intermediates (50) and (51). Like 2-ethoxybenzoxazin-4-one, the sulphur analogue (53) undergoes ethanol elimination under the influence of an acid catalyst to give the unstable cyclic acylamine (54), which can be trapped as Diels-Alder adducts... 

N-Gondensed cyclimmonium salts from cyclic acylamines... 

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