Organic Oxidations Using Geomimicry

Anaerobic oxidation of aldehydes to carboxylic acids under hydrothermal conditions

Examples of anaerobic oxidation of aldehydes in hydrothermal solutions are reported. The reaction using iron(iii) nitrate as the oxidant occurs under mild hydrothermal conditions and generates carboxylic acids in good yields. This method differs from previous studies which use atmospheric oxygen as the oxidant.

Effect of copper salts on hydrothermal oxidative decarboxylation: a study of phenylacetic acid

Efficient and selective effects of copper salts on hydrothermal oxidative decarboxylation have been discovered and studied.

Bulk gold catalyzes hydride transfer in the Cannizzaro and related reactions

Disproportionation reactions of benzaldehyde and benzyl alcohol are catalyzed by bulk gold with hot water as the only other reagent.

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

Organic-mineral interactions are widely occurring in hydrothermal environments, such as hot springs, geysers on land, and the hydrothermal vents in the deep ocean. Roles of minerals are critical in many hydrothermal organic geochemical processes. Traditional hydrothermal methodology, which includes using reactors made of gold, titanium, platinum, or stainless-steel, is usually associated with the high cost or undesired metal catalytic effects. Recently, there is a growing tendency for using the cost-effective and inert quartz or fused silica glass tubes in hydrothermal experiments. Here, we provide a protocol for carrying out organic-mineral hydrothermal experiments in silica tubes, and we describe the essential steps in the sample preparation, experimental setup, products separation, and quantitative analysis. We also demonstrate an experiment using a model organic compound, nitrobenzene, to show the effect of an iron-containing mineral, magnetite, on its degradation under a specific hydrothermal condition. This technique can be applied to study complex organic-mineral hydrothermal interactions in a relatively simple laboratory system.

Cu(i)/{Nb6O19} catalyzed N-acylation of arylacetic acids with amines under aerobic conditions

Employing a simple copper(i)/{Nb₆O₁₉} catalyst system, the reaction reported herein offers a facile process to give functionalized α-ketoamides from readily available arylacetic acids under aerobic conditions.

Carbonaceous Chondrite Meteorites: the Chronicle of a Potential Evolutionary Path between Stars and Life

The biogenic elements, H, C, N, O, P and S, have a long cosmic history, whose evolution can still be observed in diverse locales of the known universe, from interstellar clouds of gas and dust, to pre-stellar cores, nebulas, protoplanetary discs, planets and planetesimals. The best analytical window into this cosmochemical evolution as it neared Earth has been provided so far by the small bodies of the Solar System, some of which were not significantly altered by the high gravitational pressures and temperatures that accompanied the formation of larger planets and may carry a pristine record of early nebular chemistry. Asteroids have delivered such records, as their fragments reach the Earth frequently and become available for laboratory analyses. The Carbonaceous Chondrite meteorites (CC) are a group of such fragments with the further distinction of containing abundant organic materials with structures as diverse as kerogen-like macromolecules and simpler compounds with identical counterparts in Earth's biosphere. All have revealed a lineage to cosmochemical synthetic regimes. Several CC show that asteroids underwent aqueous alteration of their minerals or rock metamorphism but may yet yield clues to the reactivity of organic compounds during parent-body processes, on asteroids as well as larger ocean worlds and planets. Whether the exogenous delivery by meteorites held an advantage in Earth's molecular evolution remains an open question as many others regarding the origins of life are. Nonetheless, the natural samples of meteorites allow exploring the physical and chemical processes that might have led to a selected chemical pool amenable to the onset of life. Graphical Abstract ᅟ.