16487-62-0

Upstream product

• 16520-62-0 4-Phenyl-1-butyne 
• 74-88-4 methyl iodide 
• 40339-21-7 penta-3,4-dienyl-benzene 
• 639006-01-2 (5-chloropent-3-yn-1-yl)benzene 
• 614-45-9 tert-Butyl peroxybenzoate 
• 62839-68-3 trans-1-hexenyllithium 
• 120417-24-5 2-(3'-pentynyl)-1-iodobenzene 

Downstream Products

• 34298-75-4 hex-4-yn-1-ylbenzene 
• 1236146-64-7 (2-(2-methyl-3-(trifluoromethyl)cycloprop-1-enyl)ethyl)benzene 
• 16487-65-3 (Z)-1-phenyl-3-pentene 

Relevant academic research and scientific papers

Palladium-catalyzed methylation of terminal alkynes

In this communication, a palladium-catalyzed procedure for the methylation of terminal alkynes has been developed. With N,N,N-trimethylbenzenaminium trifluoromethanesulfonate as the methyl source, various desired products were obtained in moderate to good yields. Both aromatic and aliphatic alkynes are applicable.

On the Mechanism of the Nitrous Acid Induced Conversion of an Isopropylidene Group into an Alkyne

Exposure of an unsaturated oxime, unsubstituted in the β-position (such as 13), to sodium nitrite-aqueous acetic acid gives an alkyne (9) through a complex series of reactions that could be mechanistically related to the conversion of an isopropylidene group into an alkyne reported a few years ago.

Migratory Hydrogenation of Terminal Alkynes by Base/Cobalt Relay Catalysis

Migratory functionalization of alkenes has emerged as a powerful strategy to achieve functionalization at a distal position to the original reactive site on a hydrocarbon chain. However, an analogous protocol for alkyne substrates is yet to be developed. Herein, a base and cobalt relay catalytic process for the selective synthesis of (Z)-2-alkenes and conjugated E alkenes by migratory hydrogenation of terminal alkynes is disclosed. Mechanistic studies support a relay catalytic process involving a sequential base-catalyzed isomerization of terminal alkynes and cobalt-catalyzed hydrogenation of either 2-alkynes or conjugated diene intermediates. Notably, this practical non-noble metal catalytic system enables efficient control of the chemo-, regio-, and stereoselectivity of this transformation.

Copper-Catalyzed Propargylic Reduction with Diisobutylaluminum Hydride

A mild and efficient method for the synthesis of allenes through selective copper-catalyzed hydride addition to propargylic chlorides using commercially available diisobutylaluminum hydride has been developed. This transformation, which is promoted by a readily accessible N-heterocyclic carbene-copper complex, provides a wide range of new and versatile functionalized allenes in good to excellent yields with high regio- A nd stereoselectivities.

Multi-Metal-Catalyzed Oxidative Radical Alkynylation with Terminal Alkynes: A New Strategy for C(sp3)-C(sp) Bond Formation

A new way for C(sp3)-C(sp) cross-coupling with terminal alkynes has been developed by using a multi-metal-catalyzed reaction strategy. Alkyl radicals generated from different approaches are able to couple with terminal alkynes by judicious selection of the catalyst combination. This reaction protocol offers an efficient alternative approach for the synthesis of substituted alkynes from terminal alkynes besides traditional Sonogashira coupling. Mechanistic studies have also been carried out to clarify the role of each metal catalyst in the radical alkynylation processes. The reactions were found to go through radical reaction pathways. Synergistic cooperation of the metal catalysts is the key for controlling the reaction selectivity of alkyl radicals toward C(sp3)-C(sp) bond formation.

Transformation of Carbonyl Compounds into Homologous Alkynes under Neutral Conditions: Fragmentation of Tetrazoles Derived from Cyanophosphates

Cyanophosphates (CPs) can be easily prepared from either ketones or aldehydes, and their reaction with NaN3-Et3N·HCl results in the formation of azidotetrazoles. Under microwave irradiation, successive fragmentation of the azidotetrazoles generates alkylidene carbenes that undergo [1,2]-rearrangement and are transformed into homologous alkynes. Treatment of ketone-derived CPs with TMSN3 and Bu2SnO as catalyst in toluene at reflux directly yields the corresponding internal alkynes, whereas the reaction of aldehyde-derived CPs with NaN3-Et3N·HCl in THF at reflux or TMSN3-Bu2SnO (cat.) in toluene at reflux provides homologous terminal alkynes in good yields. These reactions take place under neutral conditions and can be successfully extended to obtain alkynes that are not usually accessible from the corresponding carbonyl compounds by the Ohira-Bestmann or Shioiri procedures, which require basic conditions.

Palladium-Catalyzed Synthesis of Alkynes via a Tandem Decarboxylation/Elimination of (E)-Enol Triflates

A mild catalytic synthesis of alkynes via a tandem Pd-catalyzed decarboxylation/elimination of enol triflates is described. Key attributes of the method include readily available starting materials, broad functional group tolerance, and the ability to access terminal, internal, and halogenated alkynes. The preliminary scope of the reaction is demonstrated on 25 different examples with yields ranging from 63% to 96%.

Rapid methylation of terminal acetylenes by the Stille coupling of methyl iodide with alkynyltributylstannanes: A general protocol potentially useful for the synthesis of short-lived 11CH3-labeled PET tracers with a 1-propynyl group

The Pd(0)-mediated rapid coupling (trapping) reaction of methyl iodide with an excess amount of alkynyltributyl-stannane has been developed with the aim to incorporate a short-lived 11C-labeled methyl group into biologically active organic compounds with a 1-propynyl structural unit.

EEFECTS OF ORGANOMETALS ON THE PALLADIUM-CATALYZED TANDEM CARBOPALLADIUM-CROSS COUPLING FOR PREPARING STEREODEFINED EXOCYCLIC ALKENES

The reaction of ω-(o-iodoaryl)- and ω-(Z-β-iodoalkenyl)alkynes with organometals containing Zr, Sn, Al, or B in the presence of a catalytic amount of a palladium-phosphine complex, such as Pd(PPh3)4, proceeds predominantly via initial cyclic carbopalladat