196597-17-8Relevant articles and documents
Synthesis of melatonin receptor agonist Ramelteon via Rh-eatalyzed asymmetric hydrogenation of an allylamine
Yamashita, Masayuki,Yamano, Toru
, p. 100 - 101 (2009)
In the course of developing a practical synthetic method for the selective melatonin MT1 /MT2 receptor agonist Ramelteon, a rhodium Josiphos complex was found to be an excellent catalyst for asymmetric hydrogenation of the key precursor, allylamine 1. Copyright
Concise Six-Step Asymmetric Approach to Ramelteon from an Acetophenone Derivative Using Ir, Rh, Cu, and Ni Catalysis
?asar, Zdenko,Cluzeau, Jér?me,Kova?evi?, Miroslav Planinc,Nettekoven, Ulrike
supporting information, (2021/10/20)
A concise six-step asymmetric synthesis of nearly enantiomerically pure ramelteon was developed from a monocyclic precursor with a 17% overall yield and a 97% ee in the asymmetric step. The synthetically challenging tricyclic 1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan core of ramelteon was assembled by using Ir-catalyzed O-vinylation and Rh-catalyzed vinyl ether annulation through directed C-H bond activation, while the chirality was introduced with enantioselective reduction of an α,β-unsaturated nitrile moiety under hydrosilylation conditions using a CuII/Walphos type catalyst. The presented methodology represents the shortest synthetic approach to ramelteon.
Synthetic method of ramelteon
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, (2019/12/02)
The invention discloses a synthesis method of ramelteon. The method comprises the following steps: based on commercially available compounds 4-amino-2,3-dihydrobenzofuran, under the reacting functionof sulfuric acid, sodium nitrite and potassium iodide, an aryl ammonia compound is converted into an aryl iodine compound; allowing the obtained aryl iodine compound to react with a bromo allyl alcohol compound under the action of a palladium catalyst, an inorganic base, a phosphine ligand, a norbornene derivative and an additive to obtain an aldehyde group-containing ramelteon intermediate; finally, the intermediate and propionamide are subjected to a reductive amination reaction under the action of trifluoroacetic acid and triethylsilane, a target compound ramelteon is obtained, the reactioncomprises three steps in total, and the total yield is 26%. Compared with the prior art, the synthesis method disclosed by the invention has the advantages that the target molecule ramelteon can be obtained from the commercially available compound 4-amino-2, 3-dihydrobenzofuran which is easy to prepare only by three steps, the synthesis steps are greatly shortened compared with other process routes, the steps are few, and the safety is high.
