Showing papers in "Organic Letters in 2013"

TL;DR: A 1,8-naphthalimide-derived fluorescent probe for H2S based on the thiolysis of dinitrophenyl ether is reported, which exhibits turn-on fluorescence detection of H 2S in bovine serum and lysosome-targetable fluorescent imaging of H1S with excellent selectivity.

TL;DR: The present photocatalytic protocol achieves highly efficient and regioselective difunctionalization of C═C bonds, leading to a variety of β-trifluoromethylamines.

TL;DR: A copper-catalyzed decarboxylative trifluoromethylation of various α,β-unsaturated carboxylic acids by using a stable and inexpensive solid, sodium trif LUM, Langlois reagent, was developed.

TL;DR: The probe is successfully demonstrated to enable the detection of hydrazine in live cells and results in the recovery of the ESIPT by removal of a free HBT moiety through subsequent substitution, cyclization, and elimination processes.

TL;DR: A versatile aerobic catalytic system (I(2) and O(2)/TBHP) for C-H functionalization is reported and the highlight of the method is a Friedel-Crafts reaction of phenols and indole with tertiary amines.

TL;DR: A cobalt catalyst has been developed for the acceptorless dehydrogenation of alcohols and applied to synthesize imines from Alcohols and amines, and deuterium labeling studies suggest that the reaction proceeds by an initial reversible alcohol dehydration step involving a cobalt hydride intermediate.

TL;DR: An efficient and concise one-pot protocol to synthesize sulfonylated quinoline N-oxides via copper-catalyzed C-H bond activation has been developed and various 2-aryl sulfonyl quinolines were obtained.

TL;DR: Dynamic covalent bonds supplied by reversible anthracene dimerization were combined with pillar[5]arene/imidazole host-guest interactions to construct double-dynamic polymers that reformed readily upon cooling or irradiation.

TL;DR: A BODIPY-based fluorescent probe, HCSe, has been successfully developed for the rapid detection of hypochlorous acid based on the specific HOCl-promoted oxidation of diphenyl selenide in response to the amount of HOCl.

TL;DR: Based on modulation of the conjugated polymethine π-electron system of a cyanine dye derivative, a ratiometric near-infared fluorescent probe (Cy7A) for hydrazine (N2H4) has been designed and synthesized and, for the first time, is visualization in living mice.

TL;DR: A facile synthetic route to dimethylsila[7]helicene by using a Lewis acid catalyzed double-cyclization reaction for construction of the twisted two phenanthrene moieties is described.

TL;DR: A general protocol for the synthesis of N-alkyl indoles has been developed via a redox neutral C-H activation strategy using a traceless nitroso directing group, achieving good to excellent regioselectivity for asymmetrically disubstituted acetylenes.

TL;DR: This reaction operates under mild conditions and provides access to a wide range of aryl and heteroaryl sulfinates, a useful and versatile class of synthetic intermediates, and one-pot protocols allowing direct access to sulfones and sulfonamides have been developed.

TL;DR: A unique function of tryptophan as a ligand as well as a quencher for recognition and fluorescent change by a metal binding event is characterized.

TL;DR: The first catalytic asymmetric isatin-involved Povarov reaction has been established and this method provides an unprecedented approach to access the enantioenriched spiro[indolin-3,2'-quinoline] scaffold with concomitant creation of two quaternary stereogenic centers in high yields and excellent stereoselectivities.

TL;DR: Abundant and cheap iron readily catalyzed the aerobic oxidative reactions of primary amines, secondary amine, benzylamines with anilines, and alcohols with amines by directly using air as the economic and safe oxidant, providing several direct, practical, and greener approaches for the preparation of useful imines.

TL;DR: A method for direct, auxiliary-assisted alkoxylation and phenoxylated benzoic acid derivatives and γ-sp(2) C-H bonds of amine derivatives is reported.

TL;DR: Yields are good to excellent, and for cyclic systems azidooxygenation occurs with excellent diastereoselectivity, and the C-radical generated after N3-radical addition is efficiently trapped by in situ generated TEMPO.

TL;DR: An efficient ruthenium(II) catalyst enabled broadly applicable oxidative alkyne annulations with electron-rich enamines to provide diversely decorated pyrroles, even in an aerobic fashion with air as the ideal oxidant.

TL;DR: A new set of reagents to access nitroolefins in a single step under metal-free conditions is disclosed, which is operationally simple and exhibits excellent E-selectivity.

TL;DR: A mild and efficient method for the synthesis of 6-(trifluoromethyl)phenanthridines through oxidative cyclization of 2-isocyanobiphenyls with CF3SiMe3 under metal-free conditions was developed.

TL;DR: Bis(imino)pyridine iron dinitrogen complexes have been shown to promote the anti-Markovnikov catalytic hydroboration of terminal, internal, and geminal alkenes with high activity and selectivity.

TL;DR: A novel Pd-catalyzed double C-S bond formation coupling reaction has been developed that provides an efficient method for the synthesis of substituted 1,4-benzothiazine derivates, which are structural elements of numerous bioactivity molecules rendering this protocol attractive to both synthetic and medicinal chemistry.

TL;DR: Carboboration of alkynes was found to take place efficiently by a three-component coupling reaction with diboron and carbon electrophiles under copper catalysis to afford diverse multisubstituted borylalkenes in a stereoselective manner.

TL;DR: Cross dehydrogenative coupling reactions occurring via base-promoted homolytic aromatic substitutions (BHASs) are reported and fluorenones and xanthones are readily prepared via CDC.

TL;DR: Azobenzenes were readily acylated at the 2-position through a Pd-catalyzed C-H functionalization from simple aromatic azo compounds and aldehydes in good yields.

TL;DR: Heteroaryl-substituted arenes and heteroarenes were efficiently amidated through ruthenium-catalyzed C-H bond functionalizations with a variety of sulfonyl azides and cationic ruthene(II) complexes proved to be most effective and allowed nitrogenations of electron-rich and electron-deficient arenes with ample substrate scope.

TL;DR: Treatment of readily available α,α-difluoro- and α-fluoroarylacetic acids with Selectfluor under Ag(I) catalysis led to decarboxylative fluorination, giving access to tri- and difluoromethylarenes applying a late-stage fluorination strategy.

TL;DR: An efficient and mechanistically interesting method for the synthesis of highly substituted isoquinolines by a Rh(III)-catalyzed hydrazone directed ortho C-H bond activation and annulation without an external oxidant is described.

TL;DR: This Ru(II)-catalyzed intermolecular o-C-H amidation of arenes in N-benzoylated sulfoximine with sulfonyl azides is demonstrated and successfully employed for the synthesis of HMR 1766.