Mild and Efficient Chemoselective Protection of Aldehydes as Dithioacetals Employing N-Bromosuccinimide
作者:Ahmed Kamal、Gagan Chouhan
DOI:10.1055/s-2002-20469
日期:——
A mild and chemoselective dithioacetalization procedure for the protection of aromatic, aliphatic, and alkenyl aldehydes in presence of catalytic amount of N-bromosuccinimide under neutral conditions is described.
Novel 1,5,3-dithiazepanes: three-component synthesis, stereochemistry, and fungicidal activity
作者:V. R. Akhmetova、N. N. Murzakova、T. V. Tyumkina、G. R. Khabibullina、I. S. Bushmarinov、L. F. Korzhova、N. F. Galimzyanova
DOI:10.1007/s11172-012-0301-5
日期:2012.11
Three-component heterocyclization of hydrazine with formaldehyde and ethane-1,2-dithiol gave previously unknown 3,3′-bi(1,5,3-dithiazepane). Its stereochemistry was determined by X-ray diffraction. The reaction with higher aliphatic aldehydes RCHO (R = Me, Et, Prn, and Bun) yielded 2,4-dialkyl-3-alkylideneamino-1,5,3-dithiazepanes. The stereochemistry of the latter was determined by 1H and 13C NMR spectroscopy and confirmed by quantum chemical calculations. Heterocyclizations of phenylhydrazine and benzylhydrazine with ethane-1,2-dithiol gave 3-amino-1,5,3-dithiazepanes only with CH2O and MeCHO as the aldehyde component. 3,3′-Bi(1,5,3-dithiazepane) and its N-adduct with MeI were found to exhibit fungicidal activity against microscopic fungi.