Stereoselective bromohydrin formation from β-hydroxy sulfoxides mediated by the pendant sulfoxide†‡

The synthesis of thiols, selenols, sulfides, selenides, sulfoxides, selenoxides, sulfones and selenones

“…Bromohydrin formation from β-hydroxy-γ,δ-unsaturated sulfoxides has been shown to proceed stereoselectively due to participation of the sulfoxide moiety. 163 Opening of the intermediate bromonium ion by the sulfoxide oxygen, followed by hydrolysis of the cyclic sulfoxonium intermediate proceeds with clean inversion at sulfur (Scheme 95). 163 Finally, a full discussion of the use of enantiomerically pure vinyl sulfoxides as temporary stereocontrol elements in 5-exotrig radical cyclisation-elimination reactions has appeared.…”

“…163 Opening of the intermediate bromonium ion by the sulfoxide oxygen, followed by hydrolysis of the cyclic sulfoxonium intermediate proceeds with clean inversion at sulfur (Scheme 95). 163 Finally, a full discussion of the use of enantiomerically pure vinyl sulfoxides as temporary stereocontrol elements in 5-exotrig radical cyclisation-elimination reactions has appeared. 164 3.2.2 Unsaturated sulfoxides and selenoxides.…”

The Rapid and Efficient Synthesis of Bromohydrins from Olefins under HBr/H2O2System by Visible Light Induced

“…3 The most common method for preparation of halohydrins involves ring opening of epoxides 4 or cyclic sulfate 5 by hydrogen halides or metalhalides. In general heterolytic additions of water and halogen to an alkene involves the use of molecular halogen, 6 N-halosuccinimides, 7-10 N-halosaccharin 11 or metal halides along with an oxidizing agent, 12 bromates oriodates(V) in combination with NaHSO3 13 or periodate mediated oxyfunctionalization of organic compounds using alkali metal halides.…”

Novel, Short, Stereospecific Synthesis of lyxo-(2R,3R,4R)-Phytosphingosine and erythro-(2R,3S)-Sphingosine

“…In contrast, the xylo - and lyxo -phytosphingosines have attracted less attention from the synthetic community . In continuation of our efforts aimed at the utilization of the pendant sulfoxide as an intramolecular nucleophile for regio- and stereoselective functionalization of olefins, , we disclose herein, the enantiospecific synthesis of lyxo -(2 R ,3 R ,4 R )-C 18 -phytosphingosine and erythro -(2 R ,3 S )-C 18 -sphingosine.…”

“…The C 13 hydrocarbon chain was introduced by the Pummerer ene reaction. 16 Thus, treatment of the sulfoxide (8) with TFAA in DCM afforded the intermediate (9), which without isolation was reacted in the same pot with 1-tridecene and SnCl 4 to yield the sulfide (10) as the only product. The configuration at the newly created one in sulfide (10) was not rigorously established, although it is expected to have the structure depicted, since it was of no consequence for the synthesis of the target molecules.…”