Web5 Nov 2024 · The thiirenium ions showed ambident reactivity toward subsequently added nucleophiles to give either disubstituted alkenes or alkynes depending on the nature of … WebThiirenium ions. N. Kharasch, in “Organic Sulfur Compounds,” Vol. 1, N. Kharasch, Ed., Pergamon Press, New York (1961); G. H. Schmid and D. G. Garratt, in “The Chemistry of …

The addition of 4-chlorobenzenesulfenyl chloride to phenyl …

Web31 Jul 2024 · The thiirenium salt [Ad 2 C 2 SCH 2 CH 2 SiMe 3] + Tf 2 N − (35) does not yield the thiirene Ad 2 C 2 S (37), the three-membered ring is cleaved, forming the alkyne (3) … Weband thiirenium structures (Figure 5). The kinetic data thus measure the anchimeric assistance of the nucleophilic thio group, as illustrated by schemes a and b in Figure 3. The correct comparison of the kinetic data reported in Figure 5 requires that the LG are the same. No data are available for the solvolyses of the vinyl cow and gate carobel

Attempts to Synthesize a Thiirane, Selenirane, and Thiirene by ...

WebThe geometry at 173 K of the thiirenium ion, a new heterocyclic unsaturated three-membered system, is described; the cation shows a pyramidal conformation. WebThe thiirenium salts [tBu2C2SR]+X− (34) and [Ad2C2SR]+X− (35, 36) are prepared from the bis‐tert‐butylacetylene (2) and bis‐adamantyl‐acetylene (3) with R=Me3SiCH2CH2 and tBuMe2SiCH2CH2. Attempts to cleave off the groups Me3SiCH2CH2, tBuMe2SiCH2CH2, and NCCH2CH2 resulted in thiiranes 27, 30. No selenirane Ad2Se (33) is formed from ... WebThe analogous thiirenium ion derived from 1,5-dithia-cyclonon-7-yne 32 could not be isolated but instead the spirocyclic compound 33 was obtained (Scheme 3). The reactions were proposed to proceed through an intermediate α-thiocarbonyl-stabilized carbene analogous to the ring opening of oxirenes ( Scheme 4 ) <2002JA8316> . cow and gate baby milk