Additions of aldehydes to metallated trans-1,3-Dithiane-S,S-dioxide under conditions of kinetic and thermodynamic control
作者:Varinder K Aggarwal、Ian W Davies、John Maddock、Mary F Mahon、Kieran C Molloy
DOI:10.1016/s0040-4039(00)94354-5
日期:1990.1
The chiral acyl anion equivalent (1) can be metallated with n-BuLi/py and reacts with aldehydes to give adducts in high yield. At −78δC the reaction is underkineticcontrol whereas at 0δC equilibration occurs with PhCHO and t-BuCHO resulting in good yields of single diastereoisomers.
Thermal decomposition and structural study of lanthanide complexes with trans-1,3-dithiane-1,3-dioxide
作者:P. Miranda Jr、M. F. Máduar、J. Zukerman-Schpector、J. R. Matos
DOI:10.1007/s10973-006-7864-z
日期:2007.3
Lanthanide picrates with 1,3-dithiane-1,3-dioxide ligand were synthesized and characterized. Thermal decomposition of these compounds by TG/DTG and DSC and structural studies were performed. It was found that the compounds are comprised in a single isomorphous series and their thermal decomposition occurs as exothermic events. The final products were found to be lanthanide dioxysulfates.
Catalytic Asymmetric Oxidation of Cyclic Dithioacetals: Highly Diastereo- and Enantioselective Synthesis of the <i>S</i>-Oxides by a Chiral Aluminum(salalen) Complex
The reaction of nonsubstituted 1,3-dithiane also proceeded in a highlyenantioselective manner to give the monoxide with a small formation of the trans-1,3-dioxide, an overoxidation product. Five-membered 1,3-dithiolanes and seven-membered 1,3-dithiepanes also underwent oxidation to give monoxides with high diastereo- and enantioselectivity. It was found that the equilibrium between the two chairlike