Ligand-Free Ru-Catalyzed Direct sp3 C–H Alkylation of Fluorene Using Alcohols

Autor:	Sandip G. Agalave, Boopathy Gnanaprakasam, Akash S Ubale, Moseen A Shaikh
Rok vydání:	2020
Předmět:	chemistry.chemical_classification 010405 organic chemistry Chemistry Alkene Organic Chemistry Borrowing hydrogen Alcohol Fluorene Alkylation 010402 general chemistry 01 natural sciences Medicinal chemistry 0104 chemical sciences Catalysis Hydroxylation chemistry.chemical_compound Yield (chemistry)
Zdroj:	The Journal of Organic Chemistry. 85:2277-2290
ISSN:	1520-6904 0022-3263
DOI:	10.1021/acs.joc.9b02913
Popis:	The sp3 C-H alkylation of 9H-fluorene using alcohol and a Ru catalyst via the borrowing hydrogen concept has been described. This reaction was catalyzed by the [Ru(p-cymene)Cl2]2 complex (3 mol %) and exhibited a broad reaction scope with different alcohols, allowing primary and secondary alcohols to be employed as nonhazardous and greener alkylating agents with the formation of environmentally benign water as a byproduct. A variety of 9H-fluorene underwent selective and exclusive mono-C9-alkylation with primary alcohols in good to excellent isolated yield (26 examples, 50-92% yield), whereas this reaction with secondary alcohols in the absence of any external oxidants furnished the tetrasubstituted alkene as the major product. Furthermore, a base-mediated C-H hydroxylation of the synthesized 9H-fluorene derivatives afforded 9H-hydroxy-functionalized quaternary fluorene derivatives in excellent yield.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::8f721fce7388500794a1934ab703a98e https://doi.org/10.1021/acs.joc.9b02913 Zobrazit plný text záznamu