27694-86-6

Upstream product

• 54315-33-2 3-acetoxy-1-octyne 
• 16635-23-7 phenyltriisopropoxytitanium(IV) 
• 693-25-4 n-pentylmagnesium bromide 
• 122044-10-4 Methanesulfinic acid (R)-1-phenyl-prop-2-ynyl ester 
• 1028374-87-9 N,N-dicyclohexyl-1-phenyloct-1-yn-3-ylamine 
• 109-72-8 n-butyllithium 
• 13633-26-6 4-phenylbut-1-en-3-yne 
• 100-52-7 benzaldehyde 
• 1607843-40-2 1-(1-phenyloct-2-yn-1-yl)pyrrolidine 
• 628-71-7 1-Heptyne 
• 591-50-4 iodobenzene 
• 116067-40-4 (±)-methyl oct-1-yn-3-yl carbonate 
• 66-25-1 hexanal 
• 536-74-3 phenylacetylene 

Downstream Products

• 1094509-45-1 (S)-(E)-1-(2-(methylthio)phenyl)-2-styrylheptan-1-one 
• 1173936-97-4 (E)-1-(2-(methylthio)phenyl)-2-(1-D-styryl)heptan-1-one 
• 1173936-69-0 (E)-1-(methylthio)-4-styrylnonan-3-one 
• 1607843-57-1 (E)-1-((1,2-diphenyloct-1-en-3-yl)oxy)-2,2,6,6-tetramethylpiperidine 
• 1607843-77-5 (Z)-1-((1,2-diphenyloct-1-en-3-yl)oxy)-2,2,6,6-tetramethylpiperidine 
• 1607843-74-2 (Z)-1-((1,2-diphenyloct-2-en-1-yl)oxy)-2,2,6,6-tetramethylpiperidine 
• 126182-20-5 C₂₀H₂₂ 

Relevant academic research and scientific papers

Pd-Catalyzed Heck-Type Reactions of Allenes for Stereoselective Syntheses of Substituted 1,3-Dienes

A highly stereoselective Pd-catalyzed Heck-type reaction of allenes in which the stereochemistry of both olefins is set simultaneously was developed. The ligand CyJohnPhos was crucial to achieving stereoselectivity, while minimizing isomerization of the starting material through hydropalladation. The stereodetermining factors were proposed to be A1,3 strain between the catalyst and allene substituent, which influences the σ-π-σ equilibrium of the coupled allene intermediate, as well as eclipsing interactions of R groups in the β-hydride elimination. Good functional group tolerance and stereoselectivities for formation of the Z,E isomer were demonstrated. The methodology was further expanded to include the regioselective formation of 2,4-dienoates and 2,4-dienamides with a variety of substitution patterns, albeit in reduced stereoselectivities favoring the E,E isomer. A plausible mechanism is proposed to account for the observed selectivities and substituent effects.

Synthesis of Allenes by Catalytic Coupling of Propargyl Carbonates with Aryl Iodides in the Presence of Diboron Species

Bimetallic copper-/palladium-catalyzed multicomponent reaction of propargyl carbonates, aryl iodides, and diboron species was studied. This procedure can be used for synthesis of di-, tri-, and tetra-substituted allenes. Using diboronic acid, the reaction

Copper-catalyzed regio- and stereoselective intermolecular three-component oxyarylation of allenes

A copper(II)-catalyzed intermolecular three-component oxyarylation of allenes using arylboronic acids as a carbon source and TEMPO as an oxygen source is described. The reaction proceeded under mild conditions with high regio- and stereoselectivity and functional group tolerance. A plausible reaction mechanism is proposed, involving carbocupration of allenes, homolysis of the intervening allylcopper(II), and a radical TEMPO trap.

Mild-condition synthesis of allenes from alkynes and aldehydes mediated by tetrahydroisoquinoline (THIQ)

A practical 1,2,3,4-tetrahydroisoquinoline (THIQ)-mediated synthesis of 1,3-disubstituted allenes from terminal alkynes and aldehydes under mild conditions in the presence of CuBr first and then ZnI2 was reported. This telescoped allene synthes

Asymmetric carbolithiation of conjugated enynes: A flow microreactor enables the use of configurationally unstable intermediates before they epimerize

We found that a flow microreactor system enables the generation of a configurationally unstable chiral organolithium intermediate and allows for its use in a reaction with an electrophile before it epimerizes. Based on this method, the enantioselective ca

Stereoretentive suzuki-miyaura coupling of haloallenes enables fully stereocontrolled access to (-)-Peridinin

Stimulated by the substantial challenge of synthesizing the complex and sensitive stereogenic allene-containing core of (-)-peridinin, the first stereocontrolled coupling of haloallenes with boronic acids has been achieved. This new method and the principles that emerged during its development stand to enable the more efficient and flexible preparation of a wide range of natural products, pharmaceuticals, and intermediates that possess a stereogenic allene motif. This new reaction was harnessed to achieve the first completely stereocontrolled total synthesis of (-)-peridinin. This synthesis was accomplished using only one reaction iteratively to assemble four fully functionalized building blocks with complete stereoretention at each initial halide or boron-bearing carbon. This synthesis elevates the capacity of the iterative cross-coupling strategy to an unprecedented benchmark. Moreover, the efficient and highly modular nature of this synthesis promises to enable systematic dissection of the heretofore enigmatic structure/function relationships that underlie the protein-like antilipoperoxidant activities of this remarkable small molecule natural product.

Gold(I)-catalyzed rearrangement of propargyl benzyl ethers: A practical method for the generation and in situ transformation of substituted allenes

A series of benzyl propargyl ethers react with a gold(I) catalyst to furnish variously substituted allenes via a 1,5-hydride shift/fragmentation sequence. This transformation is rapid and practical. It can be performed under very mild conditions (room temperature or 60 °C) using terminal as well as substituted alkyne substrates bearing a primary, secondary, or tertiary benzyl ether group. The allenes thus formed can be reacted in situ with an internal or external nucleophile, corresponding to an overall reductive substitution process, to produce more functionalized compounds.

Experimental and theoretical study of tunable 1,3-lithium shift of proparglie/allem lie species, transmetallation and Pd-catalyzed crosscoupling reactions

The highly selective tuning of the isomerization from 1-arylalka1,2-dien-l- yllithium to l-arylalka-1,2dien-3-yllithium has been realized in the deprotonation of 1-arylalk-l-yne (conditions A and B) and carbolithiation of l-arylbut-3-en-l-yne with alkyllithium (conditions C and D). Subsequent transmetallation and Pd-catalyzed Negishi coupling reactions afforded 1,1-diaryl or 1,3-diaryl alienes with high selectivity. Deuterium-labeling cross experiments indicated that an intermolecular lithiation process occurred in both 1,3-lithium shift conditions (conditions B and D). 1-Arylalka1,2-diene was confirmed experimentally to be the intermediate. A computational study at the B3LYP level for the isomerization indicated that the acidity of H at the 3-position is higher than that of the H at the 1-position of 1phenyl-l,2-butadiene. Under conditions B, (Pr2NH acts as a proton carrier to finish the 1,3-lithium shift. The overall activation barrier for the rate-determining step in the solvated models is ≈ 21.0 kcal mol-1, indicating that the isomerization is reasonable at room temperature. For the isomerization under conditions D, DFT calculations indicated that the addition of TMEDA (tetramethylethylenediamine) and HMPA (hexamethylphosphoramide) changes the global minimum of the system; among the possible mechanisms (P1-P5) considered, the mechanism catalyzed by dilithiated species (P5) is the most probable one. The overall activation barriers for isomerization in THF and TMEDA solvated models are 22.6 and 19.7 kcal mol-1, respectively, proving that the isomerization may proceed at RT in THF or at -78°C with TMEDA, due to the fact that the solvation of the additives may increase the concentration of 1-phenyl1,2-butadienyllithium monomer by a deaggregation effect.

Synthesis of mono- and 1,3-disubstituted allenes from propargylic amines via palladium-catalysed hydride-transfer reaction

Mono- and 1,3-disubstituted allenes were synthesized from the corresponding propargylamines via palladium-catalysed hydride-transfer reaction. In the current transformation, propargylic amines can be handled as allenyl anion equivalents and introduced int

Highly Stereoselective Synthesis of Chiral Alkylallenes by Organocopper(I)-Induced Anti 1,3-Substitution of Chiral Propynyl Esters

The synthesis of chiral 1,3-dialkylallenes R1CH=C=CHR2 of high enantiomeric purity, by applying homogeneous reaction between organocopper(I) reagents of type 2CuX>MgX-LiX> and chiral propynyl methanesulfonates or sulfinates at low temperatures in THF, is reported.The reactions are generally fast; typically complete conversion is obtained within a few minutes at -60 deg C.Overall, high anti stereoselectivity is observed.A plausible mechanism is put forward, and comparison is made with the stereochemistry of reactions of comparable substrates with d10 complexes, e.g. of Pd(0).