Material Safety Data Sheet Section 1. Identification of the substance Product Name: 8-Bromo-2h-1-benzopyran-2-one Synonyms: Section 2. Hazards identification Harmful by inhalation, in contact with skin, and if swallowed. Section 3. Composition/information on ingredients. Ingredient name: 8-Bromo-2h-1-benzopyran-2-one CAS number: 33491-30-4 Section 4. First aid measures Skin contact: Immediately wash skin with copious amounts of water for at least 15 minutes while removing contaminated clothing and shoes. If irritation persists, seek medical attention. Eye contact: Immediately wash skin with copious amounts of water for at least 15 minutes. Assure adequate flushing of the eyes by separating the eyelids with fingers. If irritation persists, seek medical attention. Inhalation: Remove to fresh air. In severe cases or if symptoms persist, seek medical attention. Ingestion: Wash out mouth with copious amounts of water for at least 15 minutes. Seek medical attention. Section 5. Fire fighting measures In the event of a fire involving this material, alone or in combination with other materials, use dry powder or carbon dioxide extinguishers. Protective clothing and self-contained breathing apparatus should be worn. Section 6. Accidental release measures Personal precautions: Wear suitable personal protective equipment which performs satisfactorily and meets local/state/national standards. Respiratory precaution: Wear approved mask/respirator Hand precaution: Wear suitable gloves/gauntlets Skin protection: Wear suitable protective clothing Eye protection: Wear suitable eye protection Methods for cleaning up: Mix with sand or similar inert absorbent material, sweep up and keep in a tightly closed container for disposal. See section 12. Environmental precautions: Do not allow material to enter drains or water courses. Section 7. Handling and storage Handling: This product should be handled only by, or under the close supervision of, those properly qualified in the handling and use of potentially hazardous chemicals, who should take into account the fire, health and chemical hazard data given on this sheet. Store in closed vessels. Storage: Section 8. Exposure Controls / Personal protection Engineering Controls: Use only in a chemical fume hood. Personal protective equipment: Wear laboratory clothing, chemical-resistant gloves and safety goggles. General hydiene measures: Wash thoroughly after handling. Wash contaminated clothing before reuse. Section 9. Physical and chemical properties Appearance: Not specified Boiling point: No data No data Melting point: Flash point: No data Density: No data Molecular formula: C9H5BrO2 Molecular weight: 225.0 Section 10. Stability and reactivity Conditions to avoid: Heat, flames and sparks. Materials to avoid: Oxidizing agents. Possible hazardous combustion products: Carbon monoxide, hydrogen bromide. Section 11. Toxicological information No data. Section 12. Ecological information No data. Section 13. Disposal consideration Arrange disposal as special waste, by licensed disposal company, in consultation with local waste disposal authority, in accordance with national and regional regulations. Section 14. Transportation information Non-harzardous for air and ground transportation. Section 15. Regulatory information No chemicals in this material are subject to the reporting requirements of SARA Title III, Section 302, or have known CAS numbers that exceed the threshold reporting levels established by SARA Title III, Section 313.
Gold(I)-Catalyzed Intramolecular Hydroarylation of Phenol-Derived Propiolates and Certain Related Ethers as a Route to Selectively Functionalized Coumarins and 2<i>H</i>-Chromenes
作者:Aymeric Cervi、Yen Vo、Christina L. L. Chai、Martin G. Banwell、Ping Lan、Anthony C. Willis
DOI:10.1021/acs.joc.0c02011
日期:2021.1.1
Methods are reported for the efficient assembly of a series of phenol-derived propiolates, including the parent system 56, and their Au(I)-catalyzed cyclization (intramolecular hydroarylation) to give the corresponding coumarins (e.g., 1). Simple syntheses of naturalproducts such as ayapin (144) and scoparone (145) have been realized by such means, and the first of these subject to single-crystal
A novel, practical and metal-free approach for the regioselective selenation of coumarins employing (bis(trifluoroacetoxy)iodo)benzene (PIFA) at room temperature is presented. The developed method is suitable for a wide substrate scope and affords 3-selenyl coumarins in good to excellent yields with high selectivity. A radical mechanism is proposed for this new transformation. Furthermore, the application
Derivatization of Coumarins at the Benzenoid Ring in Aqueous Medium
作者:Sankar C Bhunia、Sutanuka Pal、Gopal C Patra、Sudhir C Pal
DOI:10.1002/jhet.1800
日期:2014.11
prepared from coumarin, 7‐methylcoumarin, and 3,4‐benzocoumarin. The Reimer–Tiemann reaction, Lederer–Manasse reaction, bromination using molecular bromine as well as 2,4,4,6‐tetrabromocyclohex‐2,5‐dien‐1‐one, Elbs reaction, and diazocoupling have been carried under controlled conditions to obtain various derivatives. Further, several reactions of aldehyde derivatives of these coumarins have been carried
Reaction of salicylaldehydes (1) with carbethoxymethylenetriphenylphosphorane in diethylaniline under reflux gave coumarins (3) in moderate to high yield except 3-methoxycarbonylsalicyladehyde (1e) as summarized in Table I. The substituent effects are discussed. A substituent at C6 on 1 usually facilitated the formation of the coumarin ring regardless of its electronic character.
trifluoroacetyl group to coumarin in the presence of ethyl trifluoroacetate and the subsequent treatment with trifluoroacetic acid led to simple access to a trifluoromethylated benzofurofuranone at 8a-position with a high regio- and stereoselectivity. Trifluoromethylated or difluoromethylated benzofurofuranone derivatives were also prepared fromcoumarins including naturally occurring ones only in two successive