14001-61-7Relevant articles and documents
2-Amino-1,3,5-triazine chemistry: hydrogen-bond networks, Takemoto thiourea catalyst analogs, and olfactory mapping of a sweet-smelling triazine
Hintermann, Lukas,P?thig, Alexander,Xiao, Li
, p. 1529 - 1539 (2015)
Abstract The chemistry of 4,6-dialkyl-2-amino-1,3,5-triazines with bulky alkyl substituents was investigated and their use as building blocks for preparing chiral thiourea organocatalysts explored. Reaction of ammonia with 4,6-di-tert-butyl-2-chloro-1,3,5-triazine gave 4,6-di-tert-butyl-1,3,5-triazin-2-amine which formed extended hydrogen-bond networks in the solid state according to X-ray crystallography. Selected heterocyclic amines were converted to isothiocyanates, and the latter reacted with (S,S)-2-(dimethylamino)cyclohexylamine to give enantiopure 1-hetaryl-3-[2-(dimethylamino)cyclohexyl]thioureas, with hetaryl representing either 4,6-dimethyl-1,3-diazin-2-yl, 4,6-diisopropyl-1,3,5-triazin-2-yl, or 4,6-di-tert-butyl-1,3,5-triazin-2-yl groups. These compounds are structural analogs of Takemotos's chiral thiourea organocatalysts (1-[3,5-bis(trifluoromethyl)phenyl]-3-[(1S,2S)-2-(dimethylamino)cyclohexyl]thiourea) with an aza-aryl instead of the 3,5-bis(trifluoromethyl)phenyl group. They feature a strong intramolecular N-H to N-1 hydrogen bond, as shown by X-ray crystallography of 1-(4,6-di-tert-butyl-1,3,5-triazin-2-yl)-3-[2-(dimethylamino)cyclohexyl]thiourea in the solid state and by 1H NMR spectroscopy of all derivatives in CDCl3 solution, which prevents them from acting as bifunctional organocatalyst. In the reaction of 4,6-di-tert-butyl-2-chloro-1,3,5-triazine with ammonia, 4,6-di-tert-butyl-2-ethoxy-1,3,5-triazine was identified as side-product displaying a mildly sweet, floral odor that is unusual for a 1,3,5-triazine. Analogs (>35) of 4,6-di-tert-butyl-2-ethoxy-1,3,5-triazine were prepared to define the important structural factors of the olfactophore.
Study on the preparation of heteroaryl substituted enamines. A simple synthesis of heteroaryl substituted acetaldoximes from enamines
?opar, Anton,Stanovnik, Branko,Ti?ler, Miha
, p. 465 - 474 (2007/10/03)
A comparative study of the reactivity of methyl groups towards N,N-dimethylformamide dimethyl acetal and tert-butoxybis(dimethylamino)methane was carried out on methyl substituted six-membered nitrogen containing heterocycles 1 to give enamines 2, which were easily transformed to oximes by treating with hydroxylamine hydrochloride in methanol. Most of them were isolated as (E,Z)-oximes of heteroarylacetaldehyde (11), but 5-(1,2,4-triazinyl) substituted derivatives as (E,Z)-oximes of 2,5-dihydro-1,2,4-triazin-(Z)-5-ylideneacetaldehyde (11t, 11u, and 12). Oximes were finally transformed to the corresponding acetonitriles 16 and 3-(dimethylamino)acrylonitriles 17.
