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A synthetic method to prepare enantioenriched secondary and tertiary 3‐amido allylic alcohols efficiently that relies on their stereoablative enantioselective kinetic resolution (KR) catalysed by a chiral Brønsted acid is described. Achieved at room temperature, the stereoablative asymmetric KR protocol was shown to exhibit excellent functional group tolerance and provided product yields up to 50%, and ee and s values up to 99% and >200. The synthetic utility of the divergent catalytic protocol was exemplified by the 1 mmol scale preparation of one tertiary example and its reduction or bromination to give the corresponding 1,3‐amino alcohol and 2‐bromo‐1,3‐amino alcohol derivatives. The suggested asymmetric KR pathways provide rare instances of accomplishing enantioselective discrimination through the dehydration or imine‐enamine tautomerisation/retro‐aza‐aldol reaction of the respective 2° and 3° alcohol substrates. [ABSTRACT FROM AUTHOR]

A synthetic method to prepare 1-alkyl-substituted-pyrazolidin-3-ones efficiently that relies on the 4CzPN-mediated alkylation of azomethine imines by 4-alkyl-substituted-1,4-dihydropyridines (DHPs) under blue light emitting diode (LED) light (λmax = 456 nm) is reported. An approach that exploits the ability of blue LED light to initiate the acylation of the imine substrate by 4-acyl-substituted-DHPs to give 1-acyl-substituted-pyrazolidin-3-ones is also presented. Achieved under mild reaction conditions at room temperature, the synthetic protocol was shown to tolerate a broad range of functional groups to afford the corresponding 1-substituted-pyrazolidin-3-ones in yields up to 99%. [ABSTRACT FROM AUTHOR]

A synthetic method to prepare 1,2‐diamines efficiently that relies on the 4CzPN‐catalysed α‐aminoalkylation of azomethine imines by secondary and tertiary α‐silylamines under blue light emitting diode (LED) light (456 nm) is described. Achieved under metal‐ and additive‐free reaction conditions at room temperature, the synthetic protocol was shown to afford product yields up to 99% and applicable to the late‐stage functionalisation of three drug molecules and the gramme‐scale preparation of one example. [ABSTRACT FROM AUTHOR]

A synthetic method to prepare 2,3-dihydro-1H-benzo[f]indoles that relies on the rhodium(I)-catalysed cycloisomerisation/6π electrocyclisation of 5-(ethylnylamino)pent-2-yn-1-yl esters is described. The reaction mechanism was delineated to involve a rare instance in rhodium catalysis of an in situ formed rhodacycle that is susceptible to a formal 1,8-acyloxy migration-initiated reductive elimination. This is followed by the proposed ensuing 1,4-allenene undergoing a 6π electrocyclisation to give the N-heterocyclic product. [ABSTRACT FROM AUTHOR]

A synthetic method to prepare 11H‐benzo[a]fluorenes and 13H‐indeno[1,2‐l]phenanthrenes that relies on the gold(I)‐ and Brønsted acid‐mediated deacyloxylative cycloaromatisation of 1,6‐diyne esters under reaction conditions that did not require the exclusion of moisture or air is described. The reaction mechanism was delineated to involve an initial gold(I)‐catalysed 1,2‐acyloxy migration and 5‐exo‐trig cyclisation pathway. This was followed by 1,5‐enyne rearrangement and Brønsted acid‐assisted deacyloxylative aromatisation to give the polyaromatic hydrocarbon (PAH) product. [ABSTRACT FROM AUTHOR]

A highly efficient triflic acid catalyzed ring opening of a wide variety of 1-cyclopropyl-2-propyn-1-ols with alcohols as an efficient synthetic route to conjugated enynes is reported. The mechanism involved protonation of the alcohol substrate by the TfOH catalyst, followed by ionization of the starting material to causes ring opening of the cyclopropane moiety and trapping by the alcohol nucleophile to yield the conjugated enyne product.

Ytterbium(III) triflate-catalyzed ring opening of substituted 1-cyclopropyl-2-propyn-1-ols with sulfonamdies as an efficient route to conjugated enynes is described. The reaction is operationally straightforward and is accomplished in regioselective manner in all except one case under mild conditions.

A novel 3D ordered ferroelectric metal-organic framework (MOF), which was prepared through employing cycloaddition chiral ligand synthesis under hydrothermal reaction conditions is reported. The class of materials prepared provides a new way to examining the potential applications of MOF as ferroelectric materials.