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A catalyst-controlled vicinal amino- versus oxy-acetoxylation of alkenes with PhI(OAc)2 as the oxidant is described. The divergent synthesis of cyclic ureas and isoureas was achieved in good yields under mild conditions employing ambident urea nucleophiles. Both terminal and internal alkenes are compatible with this reaction protocol.

The synthesis of fluorinated complex molecules via direct C(sp(3))-H fluorination is attractive yet remains challenging. Here we describe the Pd(II)-catalyzed fluorination of unactivated methylene C(sp(3))-H bonds by an inner-sphere mechanism. This method allows the site- and diastereoselective fluorination of β-methylene C(sp(3))-H bonds of α-amino acid derivatives. A range of substrates containing both aliphatic and benzylic C(sp(3))-H bonds were compatible with this protocol, leading to an array of β-fluorinated α-amino acids. Stoichiometric fluorination of an isolated palladacycle intermediate takes place rapidly under very mild reaction conditions (room temperature, 5-10 min). Data from preliminary mechanistic studies are consistent with direct C-F reductive elimination from a high-valent intermediate.

Li(8)ZrO(6) contains a high lithium content and may bear a great ability of CO(2) absorption, yet the reports about the properties of CO(2) absorption on Li(8)ZrO(6) are few to date for its difficulty in production. In this paper, high-purity Li(8)ZrO(6) is synthesized via a three-step calcination method combined with an effective lithium source and a suitable initial Li/Zr molar ratio. The produced Li(8)ZrO(6) possesses a great CO(2) absorption capacity of about 53.98 wt % at 998 K, which could be well-maintained in a wide range of CO(2) partial pressures of 0.1-1.0 bar although it decreased gradually during the multicycle process of CO(2) absorption-desorption in a 10% CO(2) feed stream because of the high working temperature. These properties imply that Li(8)ZrO(6) may be a new option for high-temperature CO(2) capture applied in industrial processes such as a steam methane reformer.

Malting-quality barley samples of the varieties Harrington, Manley, and TR118, each from two locations in Saskatchewan, were collected directly from the producers and sent to China for storage. At regular intervals samples were shipped back to Canada for analysis consisting of germination studies, alpha-amylase tests, magnetic resonance imaging (MRI), and magnetic relaxation (NMR) studies. Samples showing a decrease in germinative energy and elevated levels of alpha-amylase also showed a rapid uptake of water in the area between the embryo and the endosperm as observed by MRI. Using NMR relaxation experiments, viable and nonviable barley samples could be distinguished after 2 h of imbibition.