An acid–base reaction to speed up a sluggish catalytic cycle! AcOH as the solvent enables extraordinarily fast and efficient PdII-catalysed, direct intramolecular allylic aminations, assisting benzoquinone-mediated palladium reoxidation ionisation of intermediate complexes (see scheme). The structural energetic aspects such key step cycle are illustrated by means detailed DFT analysis.

ConspectusLactones and lactams are a well-known class of natural products can be used as building blocks in organic synthesis. In addition, they found many sources synthetic drugs have broad range biological or odorant properties. Chemists create these useful compounds through palladium catalysis, which is highly efficient tool for synthesis conveniently functional group tolerant. this Account, we describe our work over the past 15 years intramolecular Pd-catalyzed allylations where tethered...

Palladium-catalyzed arylation of sulfenate anions generated from β-sulfinyl esters can take place under biphasic conditions. This hitherto unknown reaction provides a simple, mild, and efficient route to aryl sulfoxides in good yields. The development new pseudo-domino type I procedure involving sulfinylation followed by Mirozoki−Heck coupling is also described.

Arylation of various sulfenate anions generated from beta-sulfinyl esters by retro-Michael reaction in the presence palladium(0) and enantiopure ligands gave corresponding aryl sulfoxides enantio-enriched form. The Josiphos-type ligand (R)-(S)-PPF-t-Bu2 turned out to be best tested, allowing ee's up 83% a predictable sense.

Allylic sulfoxides, via [2,3]-sigmatropic rearrangement and oxidative addition of the resulting allylic sulfenate esters to Pd(0), are found be excellent precursors anions. This hitherto unknown reactivity is applied in a new Pd(0)-catalyzed domino sequence involving anion generation followed by arylation afford aryl sulfoxides.

The cyclodextrin-tetraphosphine hybrid coined α-Cytep allows turnover numbers up to 340 000 and frequencies 1 h−1 be reached in Suzuki–Miyaura reactions. These exceptional figures are clearly linked the outstanding longevity of reactive species induced by ligand illustrates rising potential cyclodextrins catalytic applications.

Palladium to make them, gold cyclize them! Gold-catalyzed cycloisomerizative hydroalkylation of N-allenyl amides affords regioselectively 4-vinyl-γ-lactams. This transformation is stereospecific and takes place with a total axis-to-center chirality transfer. The required enantioenriched amide successfully obtained from an original Pd-catalyzed dynamic kinetic asymmetric (see scheme).

An atom-economical intermolecular iron-catalyzed oxyamination of alkenes is described herein. The insertion oxygenated and nitrogenated moieties from the hydroxylamine substrate was observed with full regio- chemo-selectivity for terminal in good yields. HFIP as a solvent appeared to have synergistic effect iron catalyst promote formation oxyaminated products. Preliminary mechanistic studies suggest pathway going through an aziridination reaction followed by situ ring opening.

An iron-catalyzed lactonization reaction via intramolecular C(sp3)-H functionalization is described. The process employs easily accessible hydroxamate derivatives from which the noncommon insertion of oxygen occurred through a 1,5-hydrogen atom transfer. A mixture water and hexafluoroisopropanol as solvent appeared to be key parameter this transformation reach high selectivity efficiency.

An allylic alkylation/ring-closing metathesis domino catalytic process, wherein a palladium and ruthenium catalyst are concomitantly present in the reaction mixture from outset of reaction, is developed. Evidence for Grubbs' catalysts activity alkylation also reported.

Palladium-catalyzed allylic alkylation of sulfenate anions, generated from beta-sulfinylesters by retro-Michael reaction, can take place under biphasic conditions. This new reaction provides a simple, mild, and efficient route to allyl sulfoxides in good yields.

Learning curve: Regioselective twofold deprotection of benzylated cyclodextrins with diisobutylaluminum hydride affords products that can behave as enantiomers. For example, they act ligands for enantioselective Pd0-catalyzed reactions and their complexes display opposite circular dichroism signals (see picture). They thus be seen being inherently chiral cycle surrogates. Detailed facts importance to specialist readers are published "Supporting Information". Such documents peer-reviewed, but...

Abstract The Pd‐catalyzed intramolecular allylic alkylation of unsaturated amides to give γ‐ and δ‐lactams has been studied in the presence chiral ligands. Ligand ( R )‐3,5‐ t Bu‐MeOBIPHEP (MeOBIPHEP=6,6’‐dimethoxybiphenyl‐2,2‐diyl)bis(diphenylphosphine)) afforded best results allowed cyclization reactions take place up 94:6 enantiomeric ratio. A model Pd–allyl complex prepared through NMR spectroscopic analysis, which provided insight into processes responsible for observed ratios. DFT...

Pd(II)-catalyzed alkene aminopalladation and allylic C-H activation are two competing reaction sequences sharing the same conditions. This study aimed at understanding factors that bias one or other path in intramolecular oxidative cyclization of types N-tosyl amidoalkenes. The results obtained accord with initial generation a high-energy cyclic (5- 6-membered) aminopalladated intermediate. However, this latter species can evolve only if following specific conditions met: availability...

Functionalized imidazolidin-2-one were prepared by using an iron-catalyzed alkene oxyamination reaction. Hydroxylamine derivatives used in this atom-economical process, and the addition of external oxidant was not required. The conditions developed shown to be efficient for mono-, di-, trisubstituted double bonds, a large scope diamino alcohol precursors delivered good yields with diastereoselectivities. mechanistic pathway studied appears involve both fused aziridine carbocationic species.

Palladium-catalyzed intramolecular allylic alkylations of unsaturated EWG-activated amides can take place under phase-transfer conditions or in the presence a crown ether. These new reaction are milder and higher yielding than those previously reported. A rationalization for such an unexpected result is put forth validated by DFT-B3LYP calculations. The results suggest cyclization via counterion-free (E)-enolate TS.

Unsaturated malonyl esters underwent Pd-catalyzed intramolecular allylic alkylation to give 4-vinyl-substituted γ-lactones. In contrast the formerly studied cyclization of malonamides, this reaction could be achieved only with a substrate incorporating suitably positioned silicon moiety, which directs ionization toward desired η3-allylpalladium complex. The resulting 4-[dimethyl-(2-thienyl)silylvinyl]lactone subsequently engaged into Hiyama couplings various iodoarenes, corresponding...

Free to decide: Various 4-(alpha-styryl) gamma-lactams are synthesized in 61-88% yield by a phosphine-free palladium-catalyzed carbopalladation/allylic alkylation domino sequence (see scheme). The cyclization is totally regio- and diastereoselective favor of the 3,4-trans-disubstituted gamma-lactam. process successfully applied synthesis new aza analogue naturally occurring lignan (+)-oxo-parabenzlactone.

The synthesis of 4-amino-3-cyano-N-arylpyrazoles A based on a Thorpe-Ziegler cyclization as the key step has been achieved using microwave activation. Via new diversity-oriented synthetic pathway, these highly functionalized building blocks allowed access to various heteroaromatic scaffolds such pyrazolo-pyridines B, pyrazolo-pyrimidines C and pyrazolo-oxadiazoles D. Interestingly, platforms contain three four reactive sites that could be used for post-functionalization in order further...

Palladium-catalyzed amino and oxyacetoxylation have been developed to furnish 1,4-benzodiazepinones 1,4-benzoxazepinones through the diheterofunctionalization of alkenes.

An intra-intermolecular iron-catalyzed aminoazidation of non-activated alkenes is reported for the preparation imidazolidinone, oxazolidinone, and pyrrolidinone derivatives. The method uses cheap abundant iron as a catalyst commercially available TMSN3 an azide source. This domino process allows, in single operating step, ring-closure that generates aza-heterocycle introduction azido appendage tethered to heterocycle. conditions developed offer sustainable alternative unsymmetrical vicinal...