Sustainability in chemical synthesis is a major aspect of the current synthetic endeavors and, therefore,m imicking the biological process in the laboratory nowadays has the highest priority.T owards achieving this goal, designingorganic reactions in domino mode rathert han the multistep synthetic pathways andu sing organocatalysisi nstead of metal catalysis have received al ot of attention due to the inherenta dvantageso ft hese processes in terms of synthetic efficiencya nd sustainability.A saresult, the field of asymmetric organocatalytic domino reactions has witnessed tremendous progress in recent years.T his review attempts to summarize the latest developments in asymmetric organocatalyzed domino reactions since 2012, with the emphasis on the catalysts andr eactionm odes.D iscussions on the reactionm echanismsa nd the applications of the developed domino reactionm ethodsi nt he synthesis of biologically active molecules and natural products are also includedwhen appropriate.

Utilization of the fascinating properties of b-oxodithioesters as building blocks in heterocyclic frameworks was started a few decades ago. Its similarity and dissimilarity with b-ketoesters in terms of its synthesis or as a substrate towards synthesis makes it an interesting and emerging field of synthetic organic chemistry.Tuning of catalysts and counter substrates towards selective utilization of its multiple reacting sites was summarized in the following discussion. A diverse range of monocyclic and polycyclic heterocycles with several different heteroatoms is plotted in an easy and reader friendly manner.

A one-pot, efficient approach to quinoline synthesis, directly from 2-bromoaromatic aldehydes/ketones in a H2O–EtOH mixture involving a sequence of SNAr/reduction/annulation cascade using CuSO4-d-glucose, is devised.

The efficient, regioselective synthesis of functionalized/annulated quinolines was achieved by the coupling of 2-aminoaryl ketones with alkynes/active methylenes/α-oxoketene dithioacetals promoted by InCl(3) in refluxing acetonitrile as well as under solvent-free conditions in excellent yields. This transformation presumably proceeded through the hydroamination-hydroarylation of alkynes, and the Friedländer annulation of active methylene compounds and α-oxoketene dithioacetals with 2-aminoarylketones. In addition, simple reductive and oxidative cyclization of 2-nitrobenzaldehyde and 2-aminobenzylalcohol, respectively, afforded substituted quinolines. Systematic optimization of the reaction parameters allowed us to identify two-component coupling (2CC) conditions that were tolerant of a wide range of functional groups, thereby providing densely functionalized/annulated quinolines. This approach tolerates the synthesis of various bioactive quinoline frameworks from the same 2-aminoarylketones under mild conditions, thus making this strategy highly useful in diversity-oriented synthesis (DOS). The scope and limitations of the alkyne-, activated methylene-, and α-oxoketene dithioacetal components on the reaction were also investigated.

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An operationally simple cascade protocol has been developed for the construction of 1,2- and 1,3-dithiole derivatives from α-enolic dithioesters. 1,2-Dithioles are achieved by the reaction of dithioesters with elemental sulfur in the presence of InCl under solvent-free conditions. 1,3-Dithioles have been constructed via DABCO mediated self-coupling of dithioesters in open air enabling the formation of two new C-S bonds and one ring in a single operation in contiguous fashion. The reactions proceeded smoothly affording the desired sulfur-rich heterocycles in good to excellent yields, exhibiting gram-scale ability and broad functional group tolerance utilizing easy to handle cheap and easily available reagents. The probable mechanisms for the formation of 1,2- and 1,3-dithioles from α-enolic dithioesters have been suggested.

An efficient and highly regioselective one‐pot three‐component synthesis of previously inaccessible and synthetically demanding 3‐(cycloalkyl/alkyl/arylamino)‐5‐aryl/alkylisoxazoles has been achieved by the cyclocondensation of β‐oxo dithioesters, amines and hydroxylamine in ethanol at reflux. This transformation proceeds via an in situ generated β‐oxothioamide by the reaction of the β‐oxo dithioester and amine, which undergoes nucleophilic attack by hydroxylamine followed by intramolecular cyclization with the oxo functionality and subsequent dehydration to give 5‐substituted 3‐aminoisoxazoles as a single regioisomer in good yields. Furthermore, the mechanism of the reaction has been established experimentally and shown to be in agreement with the hard and soft (Lewis) acid and base (HSAB) theory.

We have reported an indium(0)‐mediated C sp 3–S/O cross‐coupling approach that leads to the highly regioselective alkylation of α‐enolic acetate/dithioacetate systems. This hetero cross‐coupling reaction does not require additional co‐catalyst or promoter, and the in situ generated organoindium species promotes the reaction by acting as the coupling partner of the α‐enolic acetate/dithioacetate substrates. The excellent selectivity for C‐, S‐, or O‐alkylation is solely dependent on the nucleophilic behavior of α‐enolic acetate/dithioacetate systems. These results were further supported by DFT calculations of the relative electronic energies of the substrates and products as well as the activation barriers of the respective transformations.