78831-00-2Relevant articles and documents
Thieme Chemistry Journals Awardees - Where Are They Now? A Cascade Synthesis of 1,2,4-Triazin-3(2 H)-ones Using Nitrogen-Substituted Isocyanates
Dahab, Mohammed A.,Derasp, Joshua S.,Beauchemin, André M.
, p. 456 - 460 (2017)
A cascade synthesis of 1,2,4-triazin-3(2H)-ones is reported from readily accessible α-amino ketones and phenyl carbazate as a masked N-isocyanate precursor. The mild protocol provides a simple route to products with substitution patterns which are difficult to form directly. This also presents the first N-isocyanate cascade requiring the use of acidic conditions, which accelerates formation of the hydrazone intermediate and the cyclization step. This cascade further highlights that high control can be achieved in reactions forming highly reactive N-isocyanate intermediates.
Tuning the Annulation Reactivity of Vinyl Azides and Carbazates: A Divergent Synthesis of Aza-pyrimidinones and Imidazoles
Shao, Jiaan,Liu, Xingyu,Shu, Ke,Tang, Pai,Luo, Jing,Chen, Wenteng,Yu, Yongping
supporting information, p. 4502 - 4505 (2015/09/28)
A divergent cascade annulation has been developed using readily available vinyl azides and carbazates with a wide range of substituents. Vinyl azides were successfully applied as bifunctional partners to prepare aza-pyrimidinones via 6-ring closure with c
RECYCLIZATION REACTIONS. RECYCLIZATIONS OF 3-ACYLMETHYL-2,4-THIAZOLIDINEDIONES BY THE ACTION OF NUCLEOPHILES
Shvaika, O. P.,Korotkikh, N. I.,Chervinskii, A. Yu.,Artemov, V. N.
, p. 1533 - 1543 (2007/10/02)
Four directions were established and investigated in the recyclization of 3-acylmethyl-2,4-thiazolidinediones with the participation of the side chain at the cyclic nitrogen atom and the formation of substituted 2-imidazolones or 2-oxazolones (under the influence of ammonia or hydroxides respectively), 2,5-diarylpyrazines (under the influence of methylamine), 6-monosubstituted or 2,6-disubstituted 4,5-dihydro-1,2,4-triazin-3-ones, and 5-substituted 1-amino-2-imidazolones (under the influence of hydrazine and phenylhydrazine).The directions of recyclization with hydrazines are determined by the stereochemical configuration of the intermediate hydrazones; the E-hydrazones of 3-acylmethyl-2,4-thiazolidenediones are converted into 4,5-dihydro-1,2,4-triazin-3-ones, while the Z izomers are converted into 1-amino-2-imidazolones.