Access to Indoles via Diels-Alder Reactions of 5-Methylthio-2-vinylpyrroles with Maleimides
作者:Wayland E. Noland、Nicholas P. Lanzatella、Rozalin R. Dickson、Mary E. Messner、Huy H. Nguyen
DOI:10.1002/jhet.1571
日期:2013.7
Diels–Alder reactions of 5‐methylthio‐2‐vinyl‐1H‐pyrroles with maleimides followed by isomerization gave tetrahydroindoles in moderate to good yield. Aromatization using activated MnO2 in refluxing toluene gave the corresponding 2‐methylthioindoles in good yields, and demethylthioation using Raney nickel gave the 2‐H indoles in excellent yields. The protection of the adducts produced aromatization
Pd- and Ni-Catalyzed Cross-Coupling Reactions of Functionalized Organozinc Reagents with Unsaturated Thioethers
作者:Laurin Melzig、Albrecht Metzger、Paul Knochel
DOI:10.1002/chem.201002850
日期:2011.3.1
serve as electrophiles in this cross‐coupling reaction. Aryl‐, heteroaryl‐, benzylic, and alkylzinc halides with sensitive functionalities, such as ester, nitrile, or ketone groups react at ambient temperature with unsaturated thioethers using a Ni catalyst. The corresponding Pd‐catalyzed reactions require slightly higher temperatures. Large‐scale cross‐coupling experiments (10–20 mmol) with N‐heterocycles
DMSO‐TsCl is developed for methylthiolation of various heteroarenes including pyrroles, furans, thiophenes and indoles under facile conditions. This protocol features scalable, general applicability of substrates and moderate to excellent yields. An acceptable mechanism is proposed, two of the key intermediates of proposed mechanism are detected by HRMS. Further applications of this method were also
Nonsteroidal compounds as anti-inflammatory and analgesic agents
申请人:Merck & Co., Inc.
公开号:US04434175A1
公开(公告)日:1984-02-28
5-Aroyl-4-RO-, 5-aroyl-4-RS-, 5-aroyl-4-RSO-, 5-aroyl-4-RSO.sub.2 -, or 5-pyrrylcarbonyl-pyrrole alkanoic acid have been prepared via hydrolysis of a precursor-ester after high temperature decarboxylation or from direct acidic decarboxylation of a precursor diacid. The compounds are analgesic and anti-inflammatory agents of high activities but low ulcerogenic side effects.
Photochemical Trifluoromethylation of 1-Methylimidazoles and 1-Methylpyrroles Containing Methylthio Groups
作者:Masakazu Nishida、Hiroshi Kimoto、Shozo Fujii、Yoshio Hayakawa、Louis A. Cohen
DOI:10.1246/bcsj.64.2255
日期:1991.7
The title reaction was achieved by UV (254 nm) irradiation with CF3I. The methylthio group was introduced to increase electron density and to limit available reactive sites in the rings. Following trifluoromethylation, the methylthio groups were readily removed by hydrogenolysis (Raney Ni) to give the desired trifluoromethyl heterocycles.