Glyoxal cyclic acetal

The aldehydes and ketones most commonly used are benzaldehyde, acetaldehyde, formaldehyde, and acetone. However, -butyraldehyde, n-propionaldehyde, salicylaldehyde, p-tolualdehyde, and 2-furaldehyde have also been employed. A number of unsaturated aldehydes, for example, 3,7-dimethyl-2,6-octadienal (citral) and cinnamaldehyde, have yielded cyclic acetals. Acetals have been prepared from 2-butanone, cyclohexanone, and glyoxal. ... 

Such reactions have preparative value when the halo ether is easily accessible by halogenation of an ether. For example, 2,3-dichlorodioxan and ethanol yield the cyclic acetal of glyoxal 935 and cyclic acetals of 2-chloro-4-hydroxy-butyraldehyde are formed from 2,3-dichlorotetrahydrofuran and alcohols 936, 937... 

Chiral cyclic /V,D-acetals of glyoxal and their use for preparation of a-amino acids 98SL449. 

Agrawal and co-workers" " also conducted extensive studies into the synthesis, characterization and thermal and explosive behaviour of (113) (K-56, TNABN). 2,5,7,9-Tetraazabi-cyclo[4.3.0]nonane-8-one (112) was synthesized from the direct reaction of ethylenediamine with glyoxal, followed by reaction of the resulting cyclic imine with urea in concentrated hydrochloric acid nitration of (112) was achieved in 51 % yield with a mixture of nitric acid-acetic anhydride. Agrawal showed that K-56/TNABN is significantly more resistant to hydrolytic destruction than TNGU. 

Copper-based scavengers (formation of insoluble copper sulfide) Iron-oxide-based scavengers (formation of insoluble iron sulfide) Formaldehyde/methanol (formation of water-insoluble, cyclic thio compounds) Glyoxal (formation of thio acetals and other compounds)... 

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