Umemoto's Reagent

Abstract

This feature focuses on a reagent chosen by a postgraduate, highlighting the uses and preparation of the reagent in current research spotlight Umemoto's Reagent Compiled by Huiqin LiHuiqin Li was born in Henan Province, P. R. of China, in 1988. She studied chemistry at the Northeast Normal University, Changchun, where she obtained her B.Sc. degree in 2011. She is currently pursuing her M.Sc. under the supervision of Prof. Xihe Bi. Her current research project is focused on heterocycle synthesis mediated by fluoro-containing reagents.

Recent Development of Trifluoromethyl Reagents: A Review

“…Next, it was added H 2 SO 4 in the beaker. In this cooled acid, it was added methyl anthranilate (17) and sodium nitrite that was dissolved in water. This mixture was heated (40 C) and added sequentially potassium iodide, H 2 SO 4 , sodium hydrosulfite.…”

“…So, it is important to have a diverse number of trifluoromethyl containing target molecules [11][12][13][14] and in this way, researchers are trying to continuously develop cheap and easily fabricable trifluoromethyl reagents (Scheme 1). Already some efficient methods are being used to synthesize trifluoromethyl containing substrates such as Ruppert-Prakash (TMSCF 3 ) [15], Togni reagent [16], Umemoto reagents [17], and Langlois reagent (CF 3 SO 2 Na) [18]. In these methods, trifluoromethyl either acts as electrophile [19], nucleophile [20] or as free radical [21][22][23].…”

Exploration of fluorination reagents starting from FITS reagents

“…28 (Y = S, R 1,2 = H, X = OTf and BF 4 ) have often been referred as Umemoto's reagent, with which many applications have been reported [98,99].…”

An External-Catalyst-Free Trifluoromethylation/Cyclization Strategy To Access Trifluoromethylated-Dihydroisoquinolinones/Indolines with Togni Reagent II

“…The rapid development of trifluoromethylation reactions over the past decades has largely been driven by the discovery of novel trifluoromethylating reagents . Among them are Ruppert–Prakash reagent (TMSCF 3 ) which has been widely used as a nucleophilic trifluoromethylating reagent since reported by Ruppert and co-workers in 1984; Langlois reagent (CF 3 SO 2 Na), introduced by Langlois and co-workers in 1991 for trifluoromethylation of aromatics; trifluoromethanesulfonyl chloride (CF 3 SO 2 Cl), which has been widely employed to introduce the CF 3 group into aromatic or heteroaromatic systems in photoredox catalysis since introduced by MacMillan et al in 2011; Umemoto reagents (Figure ), which have been frequently used as electrophilic trifluoromethylating reagents to react with a wide range of nucleophiles including carbanions, silyl enol ethers, enamines, anilines, phenols, phosphines, and thiolates since being developed by Umemoto and co-workers in 1990; and Togni reagents (Figure ) which had been developed by Togni and co-workers as convenient electrophilic CF 3 sources for selective trifluoromethylation of active methylene compounds, thiols, phenols, and alkylphosphines from 2006 to 2008 . Among all the CF 3 sources mentioned above, the later-developed Togni-II is especially attractive and worth mentioning, owing not only to its easy preparation, preservation, and commercially less expensive price (about $62/g) in comparison with Togni-I (about $190/g) but also to its explosive applications in the later on developed CF 3 radical-involved trifluoromethylation reactions from 2011 to present.…”