1,2-cis-β-Mannopyranosides were obtained predominantly by reactions of mannopyranosyl dimethylphosphinothioate derivatives with several alcohols in the presence of iodine and a catalytic amount of triphenylmethyl perchlorate as the activator in benzene.

Several glycopyranosyl dimethylphosphinothioates having a nonparticipating group at the C-2 position could be easily prepared by reactions of the corresponding glycopyranose and dimethylphosphinothioyl chloride using butyllithium as a base in tetrahydrofuran. These dimethylphosphinothioates are stable at room temperature and gave the corresponding α-glycosides, predominantly in good yields, by reactions with alcohols using silver perchlorate as an activator in the presence of molecular seives 4A in benzene at room temperature. Also, the combined use of iodine and a catalytic amount of triphenylmethyl perchlorate was effective for this glycosidation as a new activating system instead of silver perchlorate. Further, the synthetic intermediates of H-disaccharide and the Lewis X antigen were prepared using the present method.

The reactions of mannopyranosyl dimethylphosphinothioates and alcohols using silver perchlorate as an activator in the presence of molecular sieves 4A in benzene at room temperature gave the 1,2-trans-α-mannopyranosides in good yields. On the other hand, 1,2-cis-β-mannopyranosides could be obtained from the dimethylphosphinothioates by the combined use of iodine and 5 mol% triphenylmethyl perchlorate as an activating system. The syntheses of the derivatives of αMan(1→6)[αMan(1→3)]Man and βMan(1→4)GlcNAc units of glycoproteins by these methods are described.

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The double probe method was applied to plasma of tetrafluoroethylene (TFE) and ethylene and the electron temperature (Te) and density of positive ions (np) were measured at various discharge wattages. The probe current‐probe voltage diagrams for TFE were different from those for ethylene. The shape of its diagram indicates that a considerable number of negative ions exist in TFE plasma. The levels of np for TFE were also nearly six times greater than those for ethylene at the same discharge current. The dependence of TFE polymer deposition and the chemical structure of the polymer, based on ESCA data on discharge current, was related to Te and np measured by the probe method. The values of Te and np may not be directly related to the polymer formation in a plasma; the method provides a direct measure of plasma energy density where plasma polymerization takes place, whereas it cannot be accurately estimated by the input energy of a discharge. It was found that plasma energy density based on (npTe) for TFE plasma and that for ethylene differ significantly at the same level of input parameter (W/FM), where W is the discharge wattage, F is the volume flow rate, and M is the molecular weight of the monomer.