40697-99-2Relevant academic research and scientific papers
The through-bond interaction of a sulfur lone pair with oxygenated substituents in the thiacyclohexane framework
Andrau, Laura,White, Jonathan M.
, p. 531 - 534 (2007/10/03)
Low-temperature X-ray crystal structures were determined on a range of derivatives of 4-thiacyclohexanol 5a of varying electron demand with a view to finding evidence for a through-bond interaction between the sulfur lone pair and the oxygenated substituent. In contrast to earlier suggestions, plots of C-OR bond distance versus pKa (ROH) showed that any interaction between the sulfur and the OR group is unlikely to be of a through-bond origin. Furthermore, unimolecular solvolysis rate measurements on the nosylate ester derivative 5g showed that the sulfur actually retards the reaction slightly in comparison with the corresponding sulfur-free analogue 6. CSIRO 2005.
Efficiency of a ruthenium catalyst in metathesis reactions of sulfur-containing compounds
Spagnol, Gaelle,Heck, Marie-Pierre,Nolan, Steven P.,Mioskowski, Charles
, p. 1767 - 1770 (2007/10/03)
1,3-Dimesitylimidazol-2-ylidene ruthenium benzylidene catalyst (RuCl2(=C(H)Ph)(PCy3)(IMes)) has been successfully employed in ring-closing metathesis reactions of acyclic diene sulfides, disulfides, and dithianes and in self-cross metathesis reactions of ene-sulfides, thioethers and thiols.
A 1H and 13C NMR Study of the Structure of Sulfur-Stabilized Lithiated Allylic Carbanions
Glendenning, Lionel,Field, Leslie D.,Haynes, Richard K.
, p. 2739 - 2750 (2007/10/03)
NMR studies of the solution structures of lithiated (E)-1-(t-butylthio)but-2-ene (4) and lithiated (E)-1-(phenylthio)but-2-ene (6) are reported.The structure of lithiated (E)-1-(t-butylthio)but-2-ene (4) is best described as a transoid carbanion with the allylic carbons C1, C2, and C3 having intermediate sp2-sp3 hybridization.In (4) the heteroatom and non-allylic substituent do not play any significant role in carbanion stabilization.Lithiated (E)-1-(phenylthio)but-2-ene (6) differs from (4) in that it exhibits cis geometry about the C1-C2 bond and the phenylthio group participates in helping to stabilize allylic charge.There is a discrepancy between the geometry about the C1-C2 bond in the solution and solid structures of (4) in the presence of TMEDA.
Hydroboration. 86. Convenient Conversion of Aldehydes and Ketones into the Corresponding Alkenes via Hydroboration of their Enamines. A Remarkably Simple Synthesis of Either (Z)- or (E)-Alkenes
Singaram, Bakthan,Rangaishenvi, Milind V.,Brown, Herbert C.,Goralski, Christian G.,Hasha, Dennis L.
, p. 1543 - 1549 (2007/10/02)
Aldehydes and ketones are converted into the corresponding alkenes via hydroboration of their enamines.Hydroboration of aldehyde enamines by 9-borabicyclononane (9-BBN), followed by methanolysis, affords the corresponding terminal alkenes in 75-90percent yields.Unsaturated aldehyde enamines produce the corresponding dienes under these conditions.Enamines derived from substituted cyclic ketones and heterocyclic ketones are readily accommodated in this reaction to afford the corresponding alkenes in very good yields.The synthesis of pure (Z)- or (E)-alkenes is readily achieved from the same acyclic ketone enamine by modification of the hydroboration-elimination procedure: (A) hydroboration by 9-BBN followed by methanolysis or (B) hydroboration by borane methyl sulfide (BMS) followed by methanolysis and hydrogen peroxide oxidation.Mechanistic rationale is provided.
