20017-67-8Relevant articles and documents
Weinreb Amide as Secondary Station for the Dibenzo-24-crown-8 in a Molecular Shuttle
Gauthier, Maxime,Coutrot, Frédéric
, p. 3391 - 3395 (2019)
Here is reported the synthesis of a new molecular shuttle: it consists of a dibenzo-24-crown-8 (DB24C8) that surrounds a molecular axle containing an ammonium group and a newly considered Weinreb amide as stations. At the protonated state the DB24C8 is localized around the best ammonium station, while deprotonation-carbamoylation of the ammonium triggers the shuttling of the macrocycle around the Weinreb amide site. Further post-interlocking modification of the [2]rotaxane was attempted through the cleavage of the Weinreb amide bond using a Grignard reagent. While the non-interlocked molecular axle was cleaved after a short time in mild conditions, the Weinreb amide bond remained unaltered in the [2]rotaxane species over time, even in the presence of a larger amount of Grignard and at a higher temperature, highlighting the protection shield of the macrocycle around the encircled axle.
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Hauser et al.
, p. 916 (1958)
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Protiva
, (1951)
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Umpolung Strategy for Arene C?H Etherification Leading to Functionalized Chromanes Enabled by I(III) N-Ligated Hypervalent Iodine Reagents
Mikhael, Myriam,Guo, Wentao,Tantillo, Dean J.,Wengryniuk, Sarah E.
supporting information, p. 4867 - 4875 (2021/09/14)
The direct formation of aryl C?O bonds via the intramolecular dehydrogenative coupling of a C?H bond and a pendant alcohol represents a powerful synthetic transformation. Herein, we report a method for intramolecular arene C?H etherification via an umpoled alcohol cyclization mediated by an I(III) N-HVI reagent. This approach provides access to functionalized chromane scaffolds from primary, secondary and tertiary alcohols via a cascade cyclization-iodonium salt formation, the latter providing a versatile functional handle for downstream derivatization. Computational studies support initial formation of an umpoled O-intermediate via I(III) ligand exchange, followed by competitive direct and spirocyclization/1,2-shift pathways. (Figure presented.).
Method used for reduction of tertiary amide into alcohols and/or amines
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Paragraph 0243-0246, (2019/08/07)
The invention discloses a method used for reduction of tertiary amide into alcohols and/or amines. The method comprises following steps: tertiary amide, an alkali metal reagent, and a proton donor agent are added into an organic solvent for a following reaction selectively: when the proton donor agent is a raw material alcohol and/or inorganic salt aqueous solution, the reaction product is an alcohol compound and/or tertiary amine compound. The method is capable of realizing selective reduction of tertiary amide into alcohols and tertiary amine compounds, the yield is high, the suitable rangeis wide, operation is safe and simple, the adopted raw materials are cheap and easily available; no precious metal catalyst, toxic silanes, and flammable and combustible metal hydrides are adopted; notoxic by product is generated; reaction is more friendly to the environment; problems in the prior art that amide compound reducing method operation is complex, conditions are strict, and control ofproducts is difficult are solved.