93523-49-0

Upstream product

• 89267-73-2 2-phenyl-4-(trimethylsilyl)-3-butyn-2-ol 
• 13829-77-1 3-(trimethylsilyl)-1-phenyl-2-propyn-1-one 
• 13170-43-9 (trimethylsilyl)methylmagnesium chloride 
• 762-72-1 allyl-trimethyl-silane 
• 536-74-3 phenylacetylene 
• 1066-54-2 trimethylsilylacetylene 
• 98-86-2 acetophenone 
• 51246-20-9 1-phenyl-1-iodoethylene 
• 98-81-7 1-bromovinylbenzene 

Downstream Products

• 13120-47-3 but-1-en-3-yn-2-ylbenzene 

Relevant academic research and scientific papers

Quaternary stereocentres via an enantioconvergent catalytic SN1 reaction

The unimolecular nucleophilic substitution (SN1) mechanism features prominently in every introductory organic chemistry course. In principle, stepwise displacement of a leaving group by a nucleophile via a carbocationic intermediate enables the construction of highly congested carbon centres. However, the intrinsic instability and high reactivity of the carbocationic intermediates make it very difficult to control product distributions and stereoselectivity in reactions that proceed via SN1 pathways. Here we report asymmetric catalysis of an SN1-type reaction mechanism that results in the enantioselective construction of quaternary stereocentres from racemic precursors. The transformation relies on the synergistic action of a chiral hydrogen-bond-donor catalyst with a strong Lewis-acid promoter to mediate the formation of tertiary carbocationic intermediates at low temperature and to achieve high levels of control over reaction enantioselectivity and product distribution. This work provides a foundation for the enantioconvergent synthesis of other fully substituted carbon stereocentres.

Br?nsted Acid Catalyzed Peterson Olefinations

A mild and facile Peterson olefination has been developed employing low catalyst loading of the Br?nsted acid HNTf2. The reactions are typically performed at room temperature, with the reaction tolerant to a range of useful functionalities. Furthermore, we have extended this methodology to the synthesis of enynes.

Enantioselective Construction of Quaternary Stereogenic Centers by the Addition of an Acyl Anion Equivalent to 1,3-Dienes

We report the enantioselective formation of quaternary stereogenic centers by the intermolecular addition of malononitrile, an acyl anion equivalent, and related pronucleophiles to several 1,3-disubstituted acyclic 1,3-dienes in the presence of a Pd-PHOX catalyst. Products are obtained in up to 88% yield and 99:1 er and in most cases are formed as a single regioisomer. The products' malononitrile unit undergoes oxidative functionalization to afford β,γ-unsaturated carbonyls bearing internal olefins and α-quaternary stereogenic centers.

Gold-Catalyzed Imination/Mannich Reaction Cascades of 3-En-1-ynamides with Anilines and Aldehydes to Enable 1,5-Nitrogen Functionalizations

Gold-catalyzed imination/Mannich reaction cascades on readily available 3-en-1-ynamides enable the diastereoselective synthesis of 1,5-iminoamino compounds in a one-pot operation. The reactions work well with diversified 3-en-1-ynamides, aldehydes and anilines with good to excellent diastereoselectivities. Our control experiments indicate gold-catalyzed aminations of 3-en-1-ynamides to yield α-imino allylgold intermediates that react subsequently with iminiums to implement the Mannich reactions stereoselectively. The reactions proceed with anti-selectivity for those 3-en-1-ynamides bearing acyclic alkenes whereas syn-selectivity is seen for their cycloalkene-based analogues. An open-transition state can satisfactorily rationalize these observed stereoselectivities based on an antiperiplanar conformation.

Gold-Catalyzed Rearrangement of Alkynyl Donor-Acceptor Cyclopropanes to Construct Highly Functionalized Alkylidenecyclopentenes

A gold-catalyzed 1,7-addition-cyclization-elimination cascade sequence performed on a range of alkynyl-substituted donor-acceptor-type cyclopropanes provides facile entry to highly functionalized exo-alkylidenecyclopentenes under very mild conditions. Iso

Gem-selective cross-dimerization and cross-trimerization of alkynes with silylacetylenes promoted by a rhodium-pyridine-n-heterocyclic carbene catalyst

The gem-selective cross-dimerization and -trimerization of silylacetylenes with alkynes through C-H activation using a rhodium(I)-pyridine-N-heterocyclic carbene catalyst have been developed. This reaction is applied to various aliphatic or aromatic termi

1,2,3-Triazole: Unique ligand in promoting iron-catalyzed propargyl alcohol dehydration

A 1,2,3-traizole-promoted iron(III)-catalyzed propargyl alcohol dehydration was developed for the synthesis of conjugated enynes. The desired conjugated enynes were prepared in good to excellent yields (up to 95%) with a large substrate scope and excellen

Borostannylation of alkynes and enynes. Scope and limitations of the reaction and utility of the adducts

The utility of the hetero-bismetallating reagent 1,3-dimethyl-2- trimethylstannyl-2-bora-1,3-diazacyclopentane (1) has not been fully realized because of the hydrolytic instability of the products derived from catalyzed vicinal syn-additions to alkynes. The isolation of a variety of such adducts derived from alkynes (and also from hitherto unreported additions to 1,3-enynes) as stable boron pinacolates is reported. Examples of the applications of resulting products in tandem cross-coupling reactions and as dienes in Diels-Alder reactions are illustrated.

Alkynylboranes in the Suzuki-Miyaura coupling

The addition of B-methoxy-9-borabicyclo[3.3.1]nonane (1) to alkynyllithium reagents gives stable complexes (2) which undergo efficient Suzuki-Miyaura coupling to produce a variety of alkynyl derivatives (3).

A new synthesis of substituted fulvenes

A new fulvene synthesis results from the palladium-catalyzed [2 + 2 + 2] annulation of 1 mol of a β-substituted vinyl iodide and 2 mol of a monosubstituted acetylene. This variant of the Heck reaction tolerates a wide range of substrate substituents with