127623-84-1

Upstream product

• 104-87-0 4-methyl-benzaldehyde 
• 74-99-7 prop-1-yne 
• 16466-97-0 1-propynylmagnesium bromide 
• 590-14-7 1-bromo-1-propene 
• 4529-04-8 1-propynyl lithium 

Downstream Products

• 141062-93-3 1-methyl-4-(3-methylbuta-1,2-dien-1-yl)benzene 
• 4023-84-1 4-(p-tolyl)-3-buten-2-one 

Relevant academic research and scientific papers

Rhodium-Catalyzed C?H Activation/Annulation Cascade of Aryl Oximes and Propargyl Alcohols to Isoquinoline N-Oxides

A β-hydroxy elimination instead of common oxidization to carbonyl group in secondary propargyl alcohols was successfully developed to form 2-benzyl substituted isoquinoline N-oxides by a Rhodium-catalyzed C?H activation and annulation cascade, in which moderate to excellent yields (up to 92%) could be obtained under mild reaction conditions, along with good regioselectivity, broad generality and applicability. (Figure presented.).

Synthesis of highly substituted γ-butyrolactones by a gold-catalyzed cascade reaction of benzyl esters

Easily accessible benzylic esters of 3-butynoic acids in a gold-catalyzed cyclization/rearrangement cascade reaction provided 3-propargyl γ-butyrolactones with the alkene and the carbonyl group not being conjugated. Crossover experiments showed that the formation of the new C-C bond is an intermolecular process. Initially propargylic-benzylic esters were used, but alkyl-substituted benzylic esters worked equally well. In the case of the propargylic- benzylic products, a simple treatment of the products with aluminum oxide initiated a twofold tautomerization to the allenyl-substituted g-butyrolactones with conjugation of the carbonyl group, the olefin, and the allene. The synthetic sequence can be conducted stepwise or as a one-pot cascade reaction with similar yields. Even in the presence of the gold catalyst the new allene remains intact.

Rh(I)-catalyzed transformation of propargyl vinyl ethers into (E, Z)-dienals: Stereoelectronic role of trans effect in a metal-mediated pericyclic process and a shift from homogeneous to heterogeneous catalysis during a one-pot reaction

The combination of experiments and computations reveals unusual features of stereoselective Rh(I)-catalyzed transformation of propargyl vinyl ethers into (E,Z)-dienals. The first step, the conversion of propargyl vinyl ethers into allene aldehydes, proceeds under homogeneous conditions via a cyclization-mediated mechanism initiated by Rh(I) coordination at the alkyne. This path agrees well with the small experimental effects of substituents on the carbinol carbon. The key feature revealed by the computational study is the stereoelectronic effect of the ligand arrangement at the catalytic center. The rearrangement barriers significantly decrease due to the greater transfer of electron density from the catalytic metal center to the CO ligand oriented trans to the alkyne. This effect increases electrophilicity of the metal and lowers the calculated barriers by 9.0 kcal/mol. Subsequent evolution of the catalyst leads to the in situ formation of Rh(I) nanoclusters that catalyze stereoselective tautomerization. The intermediacy of heterogeneous catalysis by nanoclusters was confirmed by mercury poisoning, temperature-dependent sigmoidal kinetic curves, and dynamic light scattering. The combination of experiments and computations suggests that the initially formed allene-aldehyde product assists in the transformation of a homogeneous catalyst (or a cocktail of catalysts) into nanoclusters, which in turn catalyze and control the stereochemistry of subsequent transformations.

Synthesis of β-sulfanyl ketones via a tandem rearrangement-conjugate addition reaction catalyzed by a Re(V)-oxo complex

A method for synthesizing β-sulfanyl ketones via a tandem rearrangement and conjugate addition reaction has been developed. This methodology provides access to a range of β-sulfanyl ketones through the rearrangement of propargyl alcohols to the corresponding enones followed by the conjugate addition of unactivated thiols. The one-pot, tandem transformation is catalyzed by ReOCl3(OPPh3)(S(CH3)2) affording aryl and alkyl β-sulfanyl ketones in good to excellent yield.

Gold-catalyzed isomerization of unactivated allenes into 1,3-dienes under ambient conditions

We have developed a gold-catalyzed isomerization of unactivated allenes into 1,3-dienes with nitrosobenzene as an additive. This reaction proceeded almost exclusively at room temperature for highly substituted allenes. The utility of this reaction is manifested by the development of one-pot [4+2]-cycloaddition of allenes and reactive alkenes.

Substituted 4-(alka-1,2-dienylsulfinyl)morpholines: preparation and conversion into the corresponding sulfinic esters and alkynes by hydrolytic desulfinylation

By reaction with morpholine-4-sulfenyl chloride in the presence of triethylamine, several substituted propargylic alcohols were converted into the corresponding allenic sulfinamides 3.As a complementary method, some new allenic α-lithio sulfinamides were prepared and efficiently alkylated with organic halides.The boron trifluoride/etherate-catalyzed treatment of the allenic sulfinamides with simple saturated, allylic or propargylic alcohols provided the corresponding alka-1,2-dienesulfinic esters.Oxidation of various N,N-disubstituted allenic sulfinamides yielded the allenic sulfonamides.The acid-catalyzed hydrolysis or deuterolysis of the title sulfinamides provided the corresponding alkynes.Keywords: -sigmatropic rearrangement / α-allenic sulfinamide / organolithium derivative / α-allenic sulfinic ester / retro-ene reaction / sulfur dioxide elimination / alkyne

Diastereoselectivity in the [2,3]-sigmatropic rearrangement of substituted allylic N,N-dialkylamidosulfoxylates. X-ray molecular structure of [(1′) S*, (S)S*]-(2′E)-4-[[3′-(4″-bromophenyl)-1′-methyl- 2′-propenyl]sulfinyl]-morpholine

By the reaction with three N,N-dialkylamidosulfenyl chlorides 2 bearing representative sizes for the R groups on the nitrogen atom, several substituted secondary E or Z allylic alcohols (1a-h) have been converted into the corresponding pairs of diastereoisomeric allylic sulfinamides (3+-3′a-v), whose ratios have been determined by 1H NMR spectroscopy. Five cases of entirely diastereoselective [2,3]-sigmatropic rearrangement have been observed. The stereochemistry of one pure diastereoisomer 3′m has been determined by single crystal X-Ray analysis. When treated with 4-morpholinesulfenyl chloride, cyclohex-2-en-1-ol is stereoselectively converted to one diastereoisomer of the sulfinamide 5b which, by unambiguous procedures, led to the sane p.tolylsulfoxide 5a already obtained by treatment of cyclohex-2-en-1-ol with toluene-p-sulfenyl chloride.