Titanium(salen)‐Catalysed Synthesis of Di‐ and Trithiocarbonates from Epoxides and Carbon Disulfide

Abstract

The combination of a bimetallic titanium(salen) complex [Ti(salen)O]2 and either tetrabutylammonium bromide or tributylamine forms a highly active catalyst system for the reaction between epoxides and carbon disulfide to lead to di‐ and/or trithiocarbonates. Reactions can be performed at 90 °C by using just 0.5–1.0 mol % of the catalysts. The reactions proceed with the inversion of the epoxide configuration and on the basis of kinetic and spectroscopic evidence, a mechanism to account for the results is proposed.

Atom economical synthesis of di- and trithiocarbonates by the lithium tert-butoxide catalyzed addition of carbon disulfide to epoxides and thiiranes

“…52,62,63 Finally, we turned our attention to the conversion of internal epoxides 1p-u (Table 3). 52,62,63 Finally, we turned our attention to the conversion of internal epoxides 1p-u (Table 3).…”

“…We suggest the in situ formation of adduct 9 by the addition of LiO t Bu to CS 2 in the initial step. 46,52,58 Subsequently, a nucleophilic attack at the sterically less hindered β-position of epoxide 1 by the xanthogenate 9 led to 10. 4E).…”

“…Endo and Yavari reported significantly improved selectivities towards the dithiocarbonate product 2 in the presence of alkali metal salts and -hydrides as catalysts. [46][47][48][49][50][51][52] We are interested in the utilization of carbon dioxide as a C1 building block and developed one-and two component catalytic systems for the synthesis of cyclic carbonates from carbon dioxide and epoxides. [48][49][50][51][52] Even though great advances in respect of the chemo-and regioselectivity have been made, the methods reported so far often require long reaction times (up to 24 h), elevated temperatures (up to 100°C), high catalyst loadings (up to 10 mol%) and the use of solvents and/or additives.…”

Solvent-free synthesis of cyclic carbonates from CO2 and epoxides catalyzed by reusable alumina-supported zinc dichloride

“…Although CS2 is an isoelectronic heterocumulene of carbon dioxide, its reaction with epoxides has been much less explored. The reaction results, in most cases, in a mixture of the 1,3-oxathiolane-2-thione and 1,3-dithiolan-2-thione as well as in 1,3-dithiolane-2ones, 1,3-oxathiolane-2-ones, 1,3-dioxolane-2-thiones and thiiranes [102][103][104]; therefore, good functional group selectivity is the most important goal to achieve in this process. The same catalytic system optimized for the carboxylation of epoxides was tested in the thiocarboxylation variant with a minimum amount of CS2.…”

Green Catalytic Synthesis of Heterocyclic Structures Using Carbon Dioxide and Related Motifs

“…Even more recently, the same group used a Ti(IV)-salen-based catalyst at somewhat higher temperatures (90 °C) but employing much lower (co)catalyst loadings (1 mol%) [139]. Even more recently, the same group used a Ti(IV)-salen-based catalyst at somewhat higher temperatures (90 °C) but employing much lower (co)catalyst loadings (1 mol%) [139].…”