The xanthate route to lactams

Total Syntheses of Dysidealactams E and F and Dysidealactone B, Drimane-Type Sesquiterpenes Derived from a Dysidea sp. of Marine Sponge

“…Figure 2 The drimane sesquiterpene (+)-winterin (8), a logical precursor to target compounds 4, 5, and 7…”

“…As a consequence, the development of new methods for their synthesis continues apace. 8 Given the foregoing, and as part of a program concerned with developing small libraries of marine natural products that could be subjected to broad screening regimes, we undertook total syntheses of the title compounds, namely dysidealactams E (4) and F (5), and dysidealactone B (7). In doing so, we sought to identify abbreviated and flexible routes to a compound or compounds embodying the drimane framework from which rapid diversification of functionality might be achieved.…”

Visible-Light-Promoted Xanthate-Transfer Cyclization Reactions of Unactivated Olefins under Photocatalyst- and Additive-Free Conditions

“…Therefore, a protocol for the synthesis of various classes of lactams that proceeds through the unique radical chemistry of xanthates would expand structural diversity of existing lactams. Pioneering contributions from the groups of Zard, Grainger, Miranda, and others have accomplished the construction of four-, five-, six-, seven-, and eight-membered lactams by direct radical cyclization, especially the tremendous amount of work of Zard that has greatly promoted the development of xanthate transfer radical chemistry (Scheme c) . However, in most cases, organic peroxides (e.g., dilauroyl peroxide and dicumyl peroxide), high temperatures or photocatalysts (precious metal complexes or elaborate organic dyes) are usually required in such approaches (Scheme c).…”

The effect of experimental conditions on the formation of dixanthogen by triiodide oxidation in the determination of ethyl xanthate by HPLC–ICP-MS/MS

“…They are used as collectors in flotation processes where their function is to create a hydrophobic layer around the mineral particle promoting the particle's adhesion to air bubbles [1]. Xanthates are also used as precursors in a variety of different chemical syntheses [2][3][4]. However, xanthates and especially their decomposition product, carbon disulfide (CS 2 ), are hazardous to the environment.…”