285565-39-1

Upstream product

• 24395-14-0 N-(p-tolylsulfonyl)-2-phenylaziridine 
• 74-86-2 acetylene 
• 51608-60-7 N-(benzylidene)-p-methylbenzenesulfonamide 
• 106-96-7 propargyl bromide 
• 100-52-7 benzaldehyde 
• 70-55-3 toluene-4-sulfonamide 
• 850720-97-7 2-fluoro-N-(4-methylbenzenesulfonyl)benzenecarboxamide 
• 446-52-6 2-Fluorobenzaldehyde 
• 1066-54-2 trimethylsilylacetylene 
• 82745-22-0 1-phenyl-1-amino-3-butyne 
• 98-59-9 p-toluenesulfonyl chloride 

Relevant academic research and scientific papers

A convenient and efficient ring-opening reaction of aziridines with acetylenes and synthesis of dihydropyrroles

In the presence of BuOK, reaction of acetylenes with N-Ts substituted aziridines derived from both cyclic and acyclic alkenes at room temperature gave rise to homopropargylamines in good to high yields and in high regioselectivity. Not only Ph- and Me3Si-substituted acetylenes but also acetylene itself was suitable reagents. Treatment of ring-opening products with I2 and AgOAc in the presence of K2CO3 provided dihydropyrroles in high yields. One-pot synthesis of dihydropyrroles was also realized by the reaction of aziridines and phenylacetylene in the presence of NaH followed by the treatment with I2 and AgOAc.

Microwave assisted synthesis of dihydropyrrole by AgOAc catalyzed intramolecular cyclization reaction of homopropargyl amine

A series of 5-aryl dihydropyrrole was synthesized from the intramolecular cyclization reaction of homopropargyl amine in the presence of AgOAc as catalyst under microwave irradiation reaction conditions. The homopropargyl amine was prepared by the reaction of propargyl bromide with N-tosyl aldimine under a sonochemical Barbier-type reaction condition. Further aromatization reaction of 5-aryl dihydropyrrole in KOtBu/DMSO can afford 2-aryl pyrrole under microwave irradiation reaction conditions.

Stereospecific Synthesis of cis-2,5-Disubstituted Pyrrolidines via N, O-Acetals Formed by Hydroamination Cyclization-Hydroalkoxylation of Homopropargylic Sulfonamides in HFIP

We reported a novel two-step stereoselective synthesis of functionalized pyrrolidines from homopropargylic sulfonamides and nucleophiles via an isolable N,O-acetal intermediates. This reaction features mild conditions and good scope of substrates. In addition, the use of hexafluoroisopropanol, acting as a solvent, an additive, a weak nucleophile, and a good leaving group, is pivotal to the success of the method. Moreover, reactions of chiral homopropargylic sulfonamides afford only 2,5-cis-disubstituted pyrrolidines with high diastereoselectivity (up to >99:1 dr) and enantioselectivity (up to >99% ee). The overall reaction constitutes a formal 1,1-bifunctionalization of terminal alkynes, which has hitherto been reported only rarely. Additionally, this method provides efficient access to pharmaceutical intermediate and to carry out postmodification of natural products.

TMSOTf mediated '5/6-: Endo-dig ' reductive hydroamination for the stereoselective synthesis of pyrrolidine and piperidine derivatives

A TMSOTf mediated 5/6-endo-dig reductive hydroamination cascade on internal alkynylamines gave expedient, stereoselective access to pyrrolidine and piperidine derivatives. We also demonstrate that a protecting group on nitrogen has a profound effect on the reactivity as well as diastereoselectivity of the reductive hydroamination cascade.

Annelated Cyclobutanes by Fe-Catalyzed Cycloisomerization of Enyne Acetates

Cationic Fe complexes of the general type [(Ph3P)2Fe(CO)(NO)]X (X=BF4, BArF4) catalyze the redox-neutral cycloisomerization of 1,6- and 1,7-enyneacetates to afford bicyclic cyclobutanes under mild conditions in good yields and diastereoselectivities.

Hg/Pt-catalyzed conversion of bromo alkynamines/alkynols to saturated and unsaturated γ-butyrolactams/lactones via intramolecular electrophilic cyclization

Convenient and general Hg(ii)/Pt(iv) catalyzed syntheses of γ-butyrolactams and α,β-unsaturated γ-butyrolactones/lactams are described via intramolecular electrophilic cyclizations of bromoalkynes with tosylamino and hydroxyl tethers. The reaction features the use of wet solvents, the exclusion of any base and additive, mild conditions and practical yields. We also synthesised few chiral lactams through this pathway. Additionally, it is shown that the NHTs group distanced further from the homopropargylic position assists regioselective bromoalkyne hydration to yield useful α-bromoketones. Furthermore, Boc protected bromo homo propargyl amines undergo 6-endo-dig cyclization through Boc oxygen to give bromomethylene substituted oxazinones.

Gold(I)-promoted heterocyclization of internal alkynes: A comparative study of direct metallate 5-endo-dig cyclization versus a stepwise cyclization

With cationic gold catalysts, internal alkynes bearing both propargylic acyloxy groups and tosylamide pronucleophiles were found to cyclize to give either five- or six-membered ring nitrogen heterocycles. A wide variety of gold catalysts, counterions, and solvents were examined to elucidate their effect on product distribution. In most cases, the direct 5-endo-dig cyclization was found to be the major pathway leading to good yields of dehydropyrrolidine products. Alkyne substrates bearing additional normal alkyl substituents at the propargylic position gave dehydropiperidines as the major product. This pathway is thought to proceed by way of a 1,2- Rautenstrauch rearrangement to produce a vinyl gold(I) carbene, which undergoes conjugate addition by the nitrogen pronucleophile. Structural and electronic factors were studied in the nitrogen pronucleophile and in the migrating acyloxy group. Each was found to have a minor effect on the product ratio.

One-pot preparation of homopropargylic N-sulfonylamines catalyzed by zinc powder

A new one-pot method for synthesis of homopropargylic N-sulfonylamines from aldehydes catalyzed by zinc powder is described. The procedure is lauded by its simplicity, good yields, and adaptability to a wide variety of aldehydes.

Enyne metathesis/Bronsted acid-promoted heterocyclization

The "one-pot" synthesis of nitrogen heterocycles and an oxygen heterocycle by enyne metathesis and in situ cyclization is reported