Catalytic deoxygenation of epoxides and diols is underdeveloped. This reaction is appealing in the context of making value-added organics from biomass. Methyltrioxorhenium (MTO) catalyzes the conversion of epoxides and vicinal diols to olefins with dihydrogen (H(2)) as the reductant under reasonably mild conditions (150 degrees C and 80-300 psi). The only reaction byproduct is water. The reaction is selective for cis cyclic diols, signaling a mechanism of alkene extrusion from a coordinated epoxide via a metallaoxetane intermediate.

A number of molybdenum(VI) dioxo salalen complexes were prepared from the reaction of Mo(CO)(6) and salen ligands containing bulky substituents, providing a novel and facile entry to Mo-salalen compounds. Two of the complexes were characterized by single-crystal X-ray diffraction. Reduction with organic phosphines or silanes afforded the monooxo molybdenum(IV) complexes, along with dinuclear molybdenum(V) species featuring a bridged oxo ligand (mu-O). One of the dinuclear complexes as well as a molybdenum(VI) dioxo salan complex was characterized structurally. All of the molybdenum compounds except the monooxo molybdenum(IV) were fully characterized by NMR, mass spectrometry, and elemental analyses. Investigations of acetophenone and 4-Ph-2-butanone reduction with PhSiH(3) showed that all of these molybdenum oxo complexes could serve as catalysts at reasonably low loading (1 mol % Mo) and approximately 110 degrees C. The time profiles and efficacy of catalysis varied depending on the precursor form of the catalyst, Mo(VI)(O)(2) vs (O)Mo(V)-O-Mo(V)(O) vs Mo(IV)(O). Solvent effects, radical scavenger probes, and other mechanistic considerations reveal that the monooxo molybdenum(IV) is the most likely active form of the catalyst.

Studies on Sulphochlorination of Paraffins. V. Kinetic Studies on the Sulphochlorination of Pure Alkanesulphochlorides The mixtures of disulphochlorides formed by sulphochlorination of 1‐alkanesulphochlorides C4C9 may be analyzed gaschromatographically after transformation into the corresponding dimethylamides. The individual peaks could be identified in some cases with the aid of pure isomeric disulphochlorides, in other cases they were identified by analogy. The mixtures formed by sulphochlorination of the isomeric heptane sulphochlorides also could be analyzed after transformation into the dimethylamides; the identification of all peaks was possible by comparison of the mixtures obtained from different heptane sulphochlorides. For the alkane sulphochlorides studied the relative rates of sulphochlorination (with reference to n‐octane) were determined, and therefore the relative reaction rates of the individual CH‐bonds with reference to one primary CH‐bond of n‐octane could be calculated. The results show a geminal or vicinal disubstitution not to take place in noticeable amount. In position 3 or in greater distance the influence of the sulphochloride group on the reactivity of the CH‐bonds is not significant.

Studies on Sulphochlorination of Paraffins. VI. Studies on the Sulphochlorination of Individual Alkyl Chlorides The products of sulphochlorination of individual C2–C7 alkyl chlorides were studied by means of 1H‐ and 13C‐n.m.r. spectroscopy. Gaschromatographic determination of the isomers formed was possible after the reaction of the chloroalkane sulphochloride mixture with dimethyl amine in ether. In no case geminal chloroalkane sulphochlorides were formed. Vicinal chlorosulphochlorides are formed, but substitution in greater distance from the chlorine is preferred if possible. Thus higher alkyl chlorides yield only very little amounts of vicinal chloroalkane sulphochlorides. The relative rates of sulphochlorination of alkyl chlorides were determined by competitive reactions.

Die Produkte der Sulfochlorierung (Einwirkung von Chlor und SO, in CCl4 bei 0‐5°C unter Belichtung) von Alkylchloriden (I) werden mittels 1 H‐ und 13C‐NMR‐Spektroskopie untersucht.