40098-75-7Relevant academic research and scientific papers
Reinvestigation of the SNi Reaction. The Ionization of Chlorosulfites
Schreiner, Peter R.,Rague Schleyer, Paul von,Hill, Richard K.
, p. 2822 - 2829 (1993)
The decomposition of alkyl chlorosulfites (ROSOCl) has been investigated both computationally and experimentally.Semiempirical (AM1 and PM3) as well as ab initio (HF/3-21G(*), HF/6-31G*, and MP2(full)/6-31G*//MP2(full)/6-31G*) methods were employed, and the results were confirmed experimentally by NMR spectroscopy.The computations indicated that certain alkyl sulfinyl cations (ROSO(1+)) are stable and might be involved in the decomposition of chlorosulfites.Detection of these ions by 1H and 13C NMR spectroscopy in polar solvents such as acetone-d6 and acetonitrile-d3 as well as kinetic studies allowed important conclusions to be drawn about the mechanistic details of the SNi reaction.We conclude that primary alkyl chlorosulfites ionize to yield a sulfinyl cation (ROSO(1+)) and Cl(1-), whereas tertiary chlorosulfites preferentially give a carbenium ion and a chlorosulfinyl anion (OSOCl(1-)) The generation of these ion pairs is facilitated in polar solvents where the rates of decomposition of chlorosulfites are largely accelerated.The decomposition of neopentyl chlorosulfite without rearrangement and the substitution at the bridgehead position of 7,7-dimethylbicycloheptyl 1-chlorosulfite show that the loss of SO2 from ROSO(1+) must be accompanied by the attack of the chloride ion from the front side.
Stereoretentive chlorination of cyclic alcohols catalyzed by titanium(IV) tetrachloride: Evidence for a front side attack mechanism
Mondal, Deboprosad,Li, Song Ye,Bellucci, Luca,Laino, Teodoro,Tafi, Andrea,Guccione, Salvatore,Lepore, Salvatore D.
, p. 2118 - 2127 (2013/04/10)
A mild chlorination reaction of alcohols was developed using the classical thionyl chloride reagent but with added catalytic titanium(IV) chloride. These reactions proceeded rapidly to afford chlorination products in excellent yields and with preference for retention of configuration. Stereoselectivities were high for a variety of chiral cyclic secondary substrates including sterically hindered systems. Chlorosulfites were first generated in situ and converted to alkyl chlorides by the action of titanium tetrachloride which is thought to chelate the chlorosulfite leaving group and deliver the halogen nucleophile from the front face. To better understand this novel reaction pathway, an ab initio study was undertaken at the DFT level of theory using two different computational approaches. This computational evidence suggests that while the reaction proceeds through a carbocation intermediate, this charged species likely retains pyramidal geometry existing as a conformational isomer stabilized through hyperconjugation (hyperconjomers). These carbocations are then essentially "frozen" in their original configurations at the time of nucleophilic capture.
A direct and stereoretentive synthesis of amides from cyclic alcohols
Mondal, Deboprosad,Bellucci, Luca,Lepore, Salvatore D.
supporting information; experimental part, p. 7057 - 7061 (2012/01/03)
Chlorosulfites prepared in situ using thionyl chloride react with nitrile complexes of titanium(IV) fluoride to give a one-pot conversion of alcohols into amides. For the first time, amides are obtained from cyclic alcohols with stereoretention. Critical to the design of these new TiIV reactions has been the use of little-explored TiIV nitrile complexes that are thought to chelate chlorosulfites in the transition state tocreate a carbocation that is rapidly captured by the nitrile nucleophile through a front-side attack mechanism.
Synthesis and Diels-Alder Reaction of Acetylenic Sulfonate
Lee, Albert W. M.,Chan,Zhong,Lee,Yeung, Anissa B. W.
, p. 326 - 327 (2007/10/03)
The first synthesis of acetylenic sulfonate and its Diels-Alder reactions are reported.
