65763-01-1

Basic information

• Product Name: 8-iodo-7-methoxy-2H-chromen-2-one
• Synonyms: 2H-1-Benzopyran-2-one, 8-iodo-7-methoxy-; 8-Iodo-7-methoxycoumarin
• CAS NO: 65763-01-1
• Molecular Formula: C₁₀H₇IO₃
• Molecular Weight: 302.0653
• Mol File: 65763-01-1.mol
• Article Data: 2

Chemical Properties

• Boiling Point: 409.7°C at 760 mmHg
• Flash Point: 201.6°C
• Density: 1.851g/cm³
• Vapor Pressure: 6.38E-07mmHg at 25°C
• Refractive Index: 1.647
• CAS DataBase Reference: 8-iodo-7-methoxy-2H-chromen-2-one(CAS DataBase Reference)
• NIST Chemistry Reference: 8-iodo-7-methoxy-2H-chromen-2-one(65763-01-1)
• EPA Substance Registry System: 8-iodo-7-methoxy-2H-chromen-2-one(65763-01-1)

Safety Data

• Hazardous Substances Data: 65763-01-1(Hazardous Substances Data)

Upstream product

• 93198-68-6 (E)-methyl 2’-hydroxy-4’-methoxycinnamate 
• 93-35-6 7-hydroxy-2H-chromen-2-one 
• 74-88-4 methyl iodide 

Downstream Products

• 112606-76-5 osthenon 
• 109741-38-0 (1'E)-8-(3'-hydroxy-3'-methylbut-1'-enyl)-7-methoxycoumarin 
• 484-12-8 osthole 
• 1358063-68-9 8-(4-fluorophenyl)-7-methoxy-2H-chromen-2-one 
• 6545-99-9 8-(3-isopropenyloxiran-2-yl)-7-methoxy-2H-chromen-2-one 
• 6724-42-1 7-methoxy-2-oxo-2H-chromene-8-carbaldehyde 

Relevant articles and documents

Half-Sandwich Ruthenium Carbene Complexes Link trans-Hydrogenation and gem-Hydrogenation of Internal Alkynes

The hydrogenation of internal alkynes with [Cp?Ru]-based catalysts is distinguished by an unorthodox stereochemical course in that E-alkenes are formed by trans-delivery of the two H atoms of H2. A combined experimental and computational study now provides a comprehensive mechanistic picture: a metallacyclopropene (??2-vinyl complex) is primarily formed, which either evolves into the E-alkene via a concerted process or reacts to give a half-sandwich ruthenium carbene; in this case, one of the C atoms of the starting alkyne is converted into a methylene group. This transformation represents a formal gem-hydrogenation of a ?€-bond, which has hardly any precedent. The barriers for trans-hydrogenation and gem-hydrogenation are similar: whereas DFT predicts a preference for trans-hydrogenation, CCSD(T) finds gem-hydrogenation slightly more facile. The carbene, once formed, will bind a second H2 molecule and evolve to the desired E-alkene, a positional alkene isomer or the corresponding alkane; this associative pathway explains why double bond isomerization and over-reduction compete with trans-hydrogenation. The computed scenario concurs with para-hydrogen-induced polarization transfer (PHIP) NMR data, which confirm direct trans-delivery of H2, the formation of carbene intermediates by gem-hydrogenation, and their evolution into product and side products alike. Propargylic aOR (R = H, Me) groups exert a strong directing and stabilizing effect, such that several carbene intermediates could be isolated and characterized by X-ray diffraction. The gathered information spurred significant preparative advances: specifically, highly selective trans-hydrogenations of propargylic alcohols are reported, which are compatible with many other reducible functional groups. Moreover, the ability to generate metal carbenes by gem-hydrogenation paved the way for noncanonical hydrogenative cyclopropanations, ring expansions, and cycloadditions.