72038-68-7

Upstream product

• 463-49-0 1,2-propanediene 
• 4119-41-9 1-iodo-3-phenylpropan 
• 67-56-1 methanol 
• 64-17-5 ethanol 
• 50-00-0 formaldehyd 
• 1823-14-9 5-phenyl-1-pentyne 
• 66950-73-0 3-phenylpropyl 1-trifluoromethanesulfonate 

Relevant academic research and scientific papers

Catalytic C-H bond addition of pyridines to allenes by a rare-earth catalyst

The catalytic C-H addition of pyridines to allenes has been achieved for the first time by using a half-sandwich scandium catalyst, thus constituting a straightforward and atom-economical route for the synthesis of alkenylated pyridine derivatives. The reaction proceeded regio- and stereoselectively, affording a new family of alkenylated pyridine compounds which are otherwise difficult to synthesize. A cationic Sc-η2-pyridyl species was isolated and confirmed to be a key catalyst species in this transformation.

Iron-Catalyzed Contrasteric Functionalization of Allenic C(sp2)-H Bonds: Synthesis of α-Aminoalkyl 1,1-Disubstituted Allenes

An iron-catalyzed C-H functionalization of simple monosubstituted allenes is reported. An efficient protocol for this process was made possible by the use of a newly developed electron-rich and sterically hindered cationic cyclopentadienyliron dicarbonyl complex as the catalyst andN-sulfonyl hemiaminal ether reagents as precursors to iminium ion electrophiles. Under optimized conditions, the use of a mild, functional-group-tolerant base enabled the conversion of a range of monoalkyl allenes to their allenylic sulfonamido 1,1-disubstituted derivatives, a previously unreported and contrasteric regiochemical outcome for the C-H functionalization of electronically unbiased and directing-group-free allenes.

Solventless and metal-free regioselective hydrofluorination of functionalized alkynes and allenes: An efficient protocol for the synthesis of: Gem -difluorides

The combination of two easily handled, highly acidic liquid HF complex reagents, DMPU-12HF and KHSO4-13HF, generated a highly acidic fluorination system that facilitated exclusive Markovnikov addition of HF to widely functionalized alkynes, inc

Catalytic Hydroalkylation of Allenes

We have developed a catalytic method for the hydroalkylation of allenes using alkyl triflates as electrophiles and silane as a hydride source. The reaction has an excellent substrate scope and is compatible with a wide range of functional groups, including esters, aryl halides, aryl boronic esters, sulfonamides, alkyl tosylates, and alkyl bromides. We found evidence for a reaction mechanism that involves unusual dinuclear copper ally complexes as catalytic intermediates. The unusual structure of these complexes provides a rationale for their unexpected reactivity.

Catalytic Anti-Markovnikov Hydroallylation of Terminal and Functionalized Internal Alkynes: Synthesis of Skipped Dienes and Trisubstituted Alkenes

We have developed catalytic anti-Markovnikov hydroallylation of terminal and functionalized internal alkynes. In this article, we describe the development of the reaction, exploration of the substrate scope, and a study of the reaction mechanism. Synthesis of skipped dienes through the hydroallylation of terminal alkyl and aryl alkynes with simple allyl phosphates and 2-substituted allyl phosphates is described. The hydroallylation of functionalized internal alkynes leads to the formation of skipped dienes containing trisubstituted alkenes. We demonstrate that the hydroallylation of internal alkynes can be used in the regio- and diastereoselective synthesis of complex trisubstituted alkenes. A mechanism of the hydroallylation reaction is proposed, and experimental evidence is provided for the key steps of the catalytic cycle. Stoichiometric experiments demonstrate an unexpected role of lithium alkoxide in the carbon-carbon bond-forming step of the reaction. A study of the hydrocupration of internal alkynes provides new insight into the structure, stability, and reactivity of alkenyl copper intermediates, as well as insight into the source of the regioselectivity in reactions of internal alkynes.

Atom-economic, regiodivergent, and stereoselective coupling of imidazole derivatives with terminal allenes

New Rh- and Pd-catalyzed regiodivergent and stereoselective intermolecular coupling reactions of imidazole derivatives with mono-substituted allenes are herein reported. Using a RhI/Josiphos system, perfect regioselectivities and high enantiomeric excess were obtained, while a Pd II/dppf system gave linear products with high regioselectivities and high E/Z selectivities. This method permits the atom economic synthesis of valuable branched and linear allylic imidazole derivatives. Copyright

Regioselective allene synthesis and propargylations with propargyl diethanolamine boronates

"Chemical Equation Presented" The utility of propargyl diethanolamine boronates as reagents for the preparation of allenes and homopropargylic alcohols is presented. Protonolysis with TFA and electrophilic substitution with N-halosuccinimides proceeded wi

Reactions of 2,2-dialkylvinyl iodonium salt with halide ions

Reactions of (E)- and (Z)-2-methyl-5-phenyl-1-pentenyl(phenyl)iodonium (1) salts with halide ions were examined in various solvents at 50 or 60°C. The main products are those of substitution, 1-halo-2-methyl-5-phenyl-1-pentenes, mainly of inversion but involving some retained products. Varying amounts of rearranged products are also formed. Reaction follows pseudo-first-order kinetics at [1] a pre-equilibrium formation of the adduct, λ 3-haloiodane, and first-, second-, and third-order reaction pathways. The first-order rate constant for the E isomer, (E)-1, is greater than that for (Z)-1, while the opposite is the case for the second- and third-order terms. The main reaction is considered to proceed via a vinylic in-plane S(N)2 mechanism to lead to inversion while some retention routes via out-of-plane S(N)2 and/or ligand coupling mechanism are also possible. Competing rearrangement reactions occur by the β-alkyl participation and no evidence for formation of the primary vinylic cation was obtained.

Solvolysis of 2,2-dialkylvinyl iodonium salt: Alkyl participation and possibility of a primary vinylic cation intermediate

Solvolysis of (E)- and (Z)-2-methyl-5-phenyl-1-pentenyl(phenyl)iodonium tetrafiuoroborate (1·BF4) was carried out in various alcohols, acetic acid, and aqueous solutions at 60 °C. Products (after acid hydrolysis) include iodobenzene and 2-methyl-5-phenylpentanal as well as rearranged ones: 6- phenyl-2-hexanone, 6-phenyl-3-hexanone, 6-phenyl-2-hexyne, 6-phenyl- 1,2- hexadiene, and 6-phenyl-2,3-hexadiene. The products of α-elimination, including 1-methyl-3-phenyl-1-cyclopentene, were also obtained in methanol and ethanol. Solvolysis of the E isomer (E)-1 is faster than that of (Z)-1 in every solvent examined. The percentage of rearrangement is higher with (E)-1 than with (Z)-1, and the main rearranged products are those of migration of the alkyl group trans to the iodonio group, but migration of the cis alkyl group is also involved. Theoretical calculations suggest that interconversion between the secondary Vinylic cations by 1,2-hydride shift is rapid. These results show that a major heterolysis reaction occurs with β-alkyl participation to directly give a secondary vinylic cation, but stereochemistry of the unrearranged substitution products suggests that formation of the primary vinylic cation is also involved in less nucleophilic solvents like acetic acid and 2,2,2-trifluoroethanol.

Solvolysis of β,β-dialkylvinyliodonium salt: Primary vinyl cation intermediate and alkyl participation

Solvolysis of both E and Z isomers of a β,β-dialkylvinyl-(phenyl)iodonium salt gave extensively rearranged products. A mechanism involving a primary vinyl cation intermediate as well as the alkyl participation leading to secondary vinyl cations is proposed.