61693-01-4

Upstream product

• 28706-85-6 tris(dimethylamino)methylidenephosphorane 
• 104-87-0 4-methyl-benzaldehyde 
• 123-11-5 4-methoxy-benzaldehyde 
• 104-81-4 4-Methylbenzyl bromide 
• 766-97-2 4-n-methylphenylacetylene 
• 149133-52-8 (TiCl₂CP(NMe₂)3)2 
• 40739-81-9 p-tolualdehyde p-toluenesulfonylhydrazone 
• 119375-97-2 4-methylphenylacetylenemagnesium bromide 
• 143958-94-5 ethyl N-((E)-2,3-di-p-tolylcyclopropyl)carbamate 
• 143958-89-8 (E)-2,3-di-p-tolylcyclopropanecarboxylic acid 
• 188262-05-7 C₁₅H₁₈NP 
• 19493-09-5 Methylenetriphenylphosphorane 
• 14580-91-7 trimethyl(methylene)phosphorane 
• 61692-91-9 1-methyl-4-[3-(4-methylphenyl)prop-2-yn-1-yl]benzene 

Downstream Products

• 1287221-35-5 C₂₆H₂₄⁽²⁾HN 

Relevant academic research and scientific papers

Trifluoromethylation of Allenes: An Expedient Access to α-Trifluoromethylated Enones at Room Temperature

A silver(I) catalyzed regioselective trifluoromethylation of allenes using Langlois's salt (NaOSOCF3) is demonstrated. This transformation enables direct expedient access to α-trifluoromethylated acroleins, which are valuable synthons for a number of pharmaceuticals and agrochemicals containing vinyl-CF3 moieties. Versatility of this trifluoromethylation method has been established with good yield and excellent regioselectivity. Preliminary experiments and computational studies were carried out to elucidate the mechanistic insight of this protocol.

Gold(I)-catalyzed enantioselective intermolecular hydroarylation of allenes with indoles and reaction mechanism by density functional theory calculations

Chiral binuclear gold(I) phosphine complexes catalyze enantioselective intermolecular hydroarylation of allenes with indoles in high product yields (up to 90 %) and with moderate enantioselectivities (up to 63%ee). Among the gold(I) complexes examined, be

Vinylphosphonium Salts and Allenes from Carbonyl Compounds Using Titanium-Substituted Ylides

(E)-Vinylphosphonium salts are conveniently obtained from the reaction of carbonyl compounds with titanium-substituted ylide species (Me2N)3P=CHTi(OiPr)Cl2 or (Me2N)3P=CHTi(OiPr)2Cl. While a wide variety of nonenolizable aldehydes are tolerated, the steric bulk surrounding the ylide carbon limits the process to highly activated or unhindered ketones. The vinylphosphonium salts may be converted to allenes by deprotonation and condensation with a second aldehyde, thus accomplishing a two-step double olefination allene synthesis. This methodology, along with a previously reported one-pot reaction, comprises the most convenient route available for the synthesis of 1,3-disubstituted allenes. The metal-substituted ylide reagent may be generated in situ from commercially-available starting materials. Two representative vinylphosphonium salts were shown to undergo reversible isomerization to the (Z)-form upon irradiation.

The Mechanism of Double Olefination Using Titanium-Substituted Ylides

The adduct 3, derived from TiCl3(OiPr) and (Me2N)3P=CH2, engages in a complicated set of interactions with NaN(SiMe3)2 and aldehydes, resulting in the requirement to use excess amounts of both reagents for the one-pot synthesis of allenes. When TiCl2(OiPr)2 is used instead, ligand substitution reactions with NaN(SiMe3)2 are diminished and so stepwise transformations can be accomplished without excess amounts of each reagent. The selective production of vinylphosphonium salts and byproduct titanium oxides from Ti-substituted ylides and aldehydes is proposed to arise from the presence of a chloride leaving group on the metal. Isolated vinylphosphonium compounds may be deprotonated with phenyllithium to give thermally sensitive allenic phosphoranes, which have been characterized by low temperature multinuclear NMR. The reaction of allenic phosphoranes with aldehydes affords oxaphosphetane and betaine intermediates which appear to interconvert upon warming to produce allene and phosphine oxide. Dimethylamino-substituted phosphorus components are required for high yields in both steps of the allene-forming process, presumably to boost the reactivity of the hindered Ti-substituted ylide reagents and to stabilize the allenic phosphorane unit so that it may be trapped by aldehyde. The placement of chiral groups on the phosphorus methylide or aldehyde components results in low levels of enantiomeric and diastereomeric induction, respectively, during allene formation. In two cases, the diastereomeric ratios of initially-formed oxaphosphetanes have been found to differ from the diastereomeric composition of their product allenes, offering examples of the phenomenon known as "stereochemical drift". However, oxaphosphetane/betaine formation from allenic phosphorane and aldehyde has been found to be irreversible, suggesting that an intramolecular betaine olefin isomerization is responsible for the loss of stereochemical integrity during the Wittig step.

The Polarized Absoption Spectrum of 1,3-Diphenyl-1,2-propadiene: Interaction between Mutually Perpendicular Equivalent ?-Electronic Systems

The polarized UV absorption spectrum of 1,3-diphenyl-1,2-propadiene (DPA) wasx measured in a stretched polymer film at 101 K, and the polarization directions of the lectronic absorption bands were determined.Pariser-Parr-Pople (PPP) calculations extended

A New Condensation Synthesis of Allenes and Dienes

A phosphorus methylide, Ti(IV) halide alkoxide, and hindered silylamide base comprise a convenient "carbon atom" synthon for the condensation of aromatic and aliphatic aldehydes to allenes and dienes, respectively.

Electron Demand in the Transition State of the Cyclopropylidene to Allene Ring Opening

The electronic structure of the transition state for the cyclopropylidene to allene conversion has been probed.The methodology involved the relative rates of ring opening vs trapping by MeOH for a series of variously substituted 2,3-diarylcyclopropylidenes.With the assumption that the rate of trapping was unaffected by substituents, a Hammett correlation was constructed.The negative value (-0.72) for ρ indicated that the carbenic center attracts electron density in the ring-opening transition state, much like the cyclopropyl cation to allyl cation transition state.Temperature-dependent studies showed that the observed preference for ring opening was driven by entropy factors.Also, using reasonable estimates for the close to diffusion-controlled trapping activation enthalpies, the derived enthalpies for ring opening were in close agreement with the best theoretical values.