Transition-metal-catalyzed hydrogen-transfer reactions have been used for the conversion of alcohols into benzimidazoles and aldehydes into benzoxazoles and benzothiazoles.

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The oxidation of alcohols to their corresponding carbonyl compounds is a frequently employed fundamental organic transformation in synthetic laboratories and the chemical industry. 1 One of the most historic and widely used methods for alcohol oxidation involves the activation of dimethylsulfoxide (DMSO) by a variety of electrophilic reagents such as oxalyl chloride (Swern oxidation), dicyclohexylcarbodiimide (Pfitzner-Moffat), SO 3 .pyridine (Parikh-Doering), trifluoroacetic acid anhydride (Omura-Sharma-Swern) and N-chlorosuccinimide (Corey-Kim oxidation with dialkyl sulfide). 2 Among these DMSO-activation methods, Swern oxidation has regularly been the default pathway due to its consistent efficiency over a broad range of substrates. 2 The original Swern oxidation employed oxalyl chloride to form the reactive chlorodimethylsulfonium chloride, which subsequently reacted with alcohols and bases to give the carbonyl compounds and dimethyl sulfide. 3 The activation of DMSO by oxalyl chloride is strongly exothermic and violently generates toxic gases such that it has to be carried out at very low temperature in a well-ventilated area. 2-4 Furthermore, oxalyl chloride itself is a volatile toxic reagent that can be difficult to handle. There have been several studies investigating other chloride-bearing reagents for the replacement of oxalyl chloride in Swern-type oxidation reactions, most notably cyanuric chloride 4 and triphenylphosphine dichloride. 1 These reagents consist of reactive chlorides bonding to a heterocycle (cyanuric six-membered ring) or heteroatom (phosphorus in phosphine dichloride). Herein, we report the use of 1,1-dichlorocycloheptatriene (1) (Scheme 1), a simple chlorinated hydrocarbon, as a new DMSO activator for efficient Swern-type oxidation of a broad range of alcohol substrates under mild reaction conditions.

A ruthenium-catalysed oxidation of alcohols by hydrogen transfer has been coupled with organocatalysed condensations using pyrrolidine or piperidine, to give a,b-unsaturated esters and nitroalkenes. Reactions proceed with high (E)-selectivity and provide an efficient and straightforward route to a,b-unsaturated compounds.

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A standard high-solids vessel (SHSV) concept design approach using pulse jet mixers (PJM) has been proposed by the US Department of Energy (DOE) for the Hanford Tank Waste Treatment and Immobilization Plant (WTP) as a potential replacement for several vessels that will be used to process highly radioactive waste. To assist with the evaluation of the SHSV concept, at DOE’s direction, the WTP Project recently completed qualification testing of the SHSV PJM mixing system to verify the design. Testing of the SHSV design, conducted at full scale, was split into two phases. The first phase of testing developed PJM controls that supported all operational modes under a set of most adverse fluid conditions. The second phase of testing used the PJM operating strategy, established during the first phase, to perform qualification testing to verify that the mixing system design supports the transfer, de-inventory, throughput, and sampling functional requirements of the SHSV. The different control methods that were used to operate PJMs in simulants exhibiting Newtonian and non-Newtonian rheological properties with high solids loading are presented. The PJM system of the SHSV uses six pulse tubes distributed in a circular array. Each pulse tube (3000 liters nominal volume) is connected to a jet pump pair (JPP) by means of an air link line. The JPP powers the PJM operation by applying a vacuum to refill the PJM (suction phase), pressurizing the PJM to discharge the pulse tube content at a target velocity (drive phase), and releasing the compressed air to allow the PJM to depressurize into a ventilation system (vent phase) designed for contaminated air. A PJM control system was developed to maximize the PJM operation and minimize potential impact to the structural integrity of the vessel. The experimental results showed effective control of the system parameters. The system response demonstrated reliable control of the drive set pressure, the drive time, and synchronization. The PJM control system design also proved robust in mobilizing settled solids.

018ChemInform Abstract Single electron transfer between Ru(NH3)63+ and Ru(NH3)62+ at a Pt electrode in liquid NH3 closely follows Nernstian behavior during the first voltammetric cycle if the voltage sweep rate is low. Deviation from voltammetric reversibility is observed with increasing voltage ramp rate, Ru(III) concentration, and increasing number of applied voltammetric cycles. XPS results obtained for the Pt surface after anodic polarization at potentials > 0.3 V reveal that the Pt surface is oxidized in liquid NH3 to a gold-colored compound containing equimolar amounts of Pt(II) and Pt(IV).