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This microreview summarizes the use of deep eutectic solvents (DES) and related melts in Organic Synthesis. This type of solvents combine the great advantages of other proposed environmentally benign alternative solvents, such as low toxicity, high availability, low inflammability, high recyclability, low volatility and low price, avoiding many disadvantages of these neoteric media. The fact that many of the components of the mixture come directly from Nature assures their biodegradability and renewability. The classification and distribution of the reactions in different sections along this microreview, as well as the emphasis paid to their scope, easily allows a general reader to understand the actual state of art, and the great opportunities opened, not only for academic proposes but also for industry.

The hydrogen autotransfer process involves an initial oxidative hydrogen elimination, followed by different types of reactions, and is completed with a reductive hydrogen addition to give the final product. The sequence allows the alkylation of different nucleophilic agents using environmentally benign alcohols as electrophiles, mild conditions, and soft bases, with water produced as the only waste material. Recent examples of modulating the organometallic catalyst have also lent themselves to expansion of the range of available substrates, as described in this Minireview.

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Asymmetric multicomponent reactions involve the preparation of chiral compounds by the reaction of three or more reagents added simultaneously. This kind of addition and reaction has some advantages over classic divergent reaction strategies, such as lower costs, time, and energy, as well as environmentally friendlier aspects. All these advantages, together with the high level of stereoselectivity attained in some of these reactions, will force chemists in industry as in academia to adopt this new strategy of synthesis, or at least to consider it as a viable option. The positive aspects as well as the drawbacks of this strategy are discussed in this Review.