Reaction and Characterization of Thioamide Dianions Derived from N-Benzyl Thioamides

Abstract

Thioamide dianions were generated by the highly efficient reaction of N-benzyl thioamides with 2 equiv of BuLi. Alkylation, allylation, and silylation took place selectively at the carbon atom adjacent to the nitrogen atom of the thioamide dianions. Oxiranes and an aldehyde were also used as electrophiles in the reaction of thioamide dianions to form N-thioacyl 1,3- or 1,2-amino alcohols. The insertion reaction of elemental sulfur to a thioamide dianion and subsequent ethylation afforded a N-thioacyl hemithioaminal. NMR studies on the thioamide mono- and dianions derived from N-benzyl 2-methoxythiobenzamide showed a linear relationship between the chemical shifts of all carbon atoms of thioamide mono- and dianions. The results also suggested that the negative charge at the benzylic carbon atom of the dianion is not fully delocalized. The charge distribution patterns of the dianion are consistent with those of pi polarization.

Thiolate-Thione Redox-Active Ligand with a Six-Membered Chelate Ring via Template Condensation and Its Pt(II) Complexes

“…The inability to access free H­(cta Ph ) is comparable to HSacSac, the unstable sulfur analogue of the ubiquitous and commercially available acetylacetone ligand, Hacac. Few derivatives have been reported, but a Pd dithio-β-diketonate complex with tert -butyl substitution, [Pd­(S,S-tmhd) 2 ] (tmhd = tetramethyl-3,5-heptanedithione), has been structurally characterized, and the ligand-centered electrochemistry of these complexes has been predicted and subsequently reported. , Alkylated versions, the thioethers R­(cta Ph ), VI , have been prepared and characterized …”

Transformation of RN=CHPh to R(R′3Si)NCH2Ph in the Catalytic Desulfurization of Secondary Thioamide with R′3SiH Promoted by an Iron Complex

“…Most chemicals were commercially available except thioamides 2 , 3 , and 4 . Thioamides 2 and 4 were synthesized according to the literature methods . IR spectra were recorded on a Perkin‐Elmer Spectrum One spectrometer.…”

Synthesis and Applications of Chalcogenoamide: Thio-, Seleno- and Telluroamides

“…Thioamide dianions (generated by the highly efficient reaction of Nbenzyl thioamides with 2 equiv. of BuLi) take place alkylation, allylation and silylation selectively at the carbon atom adjacent to the nitrogen atom of the thioamide dianions [77] (Scheme 31).…”