Methanesulfonic ethylene derivatives

Tri(cyclopentyl)borane in diglyme added at 0° to Li-n-hexylacetylide under hexane, the volatile solvent removed, methyl tosylate added at -78°, the cooling bath removed, warmed 2 hrs. at 40°, then oxidized with alkaline H2O2 -> product. Y 88%. F. e., also with other alkylating agents such as bromides, sulfates, or oxonium salts, protonation with methanesulfonic acid, and synthesis of mixtures of cis- and trans-ethylene derivs., s. A. Pelter, C. R. Harrison, and D. Kirkpatrick, Chem. Commun. 1973, 544. 

Synthesis of polyoxyethylene sterol was first reported by Scotney and Truter [6] in 1971. They simply mixed cholesterol and the appropriate amount of ethylene oxide in a sealed vial during 4 months. Later workers have applied more sophisticated methods to synthesize better defined products. Khachadurian et al. [7] synthesized both polyoxyethylene and methoxypolyoxyethylene derivatives of cholesterol. The former reaction was carried out in dichloromethane using boron trifluoride as catalyst. Derivatives with a methoxy terminal were prepared by condensing methoxypoly(oxyethylene)methanesulfonate with cholesterol in xylene. Commercially available products are produced by the reaction of sterol with ethylene oxide, resulting in a product with a distribution in the number of ethylene oxide (EO) units in the hydrophilic group. Meissner et al. also described the synthesis of sterol sulfate and sulfonate with oxy-ethylene spacers [8], The synthesis of sterol surfactants has been covered in a review by Folmer [9]. There are only a few producers of polyoxyethylene... 

---