We disclose herein an efficient photochemical formal [3+2+1] annulation strategy for the transformation of diazocarbonyl compounds into various fluorinated nitrogen-containing heterocycles. This is characterized by reacting fluoroalkyl radicals with α-diazoketones, which are used as infrequent denitrogenated synthons under visible light. Moreover, a wide range N-heterocycles containing precious CF3 and perfluoroalkylated groups constructed in moderate to good yields. Notably, this may...

A novel iodine-promoted difunctionalization of α-C sites in enaminones was demonstrated as a means synthesizing variety fully substituted thiazoles by constructing C–C(CO), C–S, and C–N bonds. This transformation allows the realization unusual aryl C2 synthons simultaneously thioylation dicarbonylation sites. preliminary mechanistic study performed indicated that cleavage C═C bonds involves bicyclization/ring-opening oxidative coupling sequence.

The first synthesis of 2,3-diaroyl quinolines via a formal [3 + 2 1] cycloaddition enaminones, aryl methyl ketones, and amines is disclosed. This reaction efficiently affords 1,4-dicarbonyl scaffold, which useful building block for constructing complex fused heterocycles. Furthermore, the scaffold has been used directly to prepare pyridazino[4,5-b]quinoline skeletons in one-pot.

Abstract The total synthesis of (+)‐cavicularin is described. features an enantio‐ and regioselective pyrone Diels–Alder reaction a vinyl sulfone to construct the cyclophane architecture natural product. substrate was prepared by one‐pot three‐component Suzuki non‐symmetric dibromoarene.

An efficient and practical de novo synthesis of pyrrole-2-carbaldehyde skeletons featuring oxidative annulation Csp3–H to C═O oxidation is presented, exemplified by the preparation derivatives from aryl methyl ketones, arylamines, acetoacetate esters. Preliminary mechanistic investigations indicate that aldehyde oxygen atom originates oxygen. Moreover, developed scalable approach provides a distinct advantage over traditional functionalization C–H moieties, avoiding use stoichiometric...

An I2-promoted domino bicyclization approach via multiple sequential C-H functionalization was serendipitously discovered for the synthesis of 1,2-fused oxindoles from methyl ketones and anilines. This optimized, resulting in a concise atom-economical one-pot construction anilines rather than using preexisting indolin-3-ones or indoles. Mechanistic studies revealed that key step involved an oxidative cross-coupling between situ generated phenylglyoxal α,α-diaminoketone.

A synergistic I2/amine promoted formal [4 + 2] cycloaddition of methyl ketones, arylamines, and aryl(alkyl)acetaldehydes as alkene surrogates has been established. This protocol allowed the modular synthesis various 2-acyl-3-aryl(alkyl)quinolines, rather than 2,4-substituted quinolines. Notably, arylamines not only participated reactants in this reaction but also acted indispensable catalysts to promote enamine formation. Moreover, mechanistic investigation suggested that occurred via an...

A short enantioselective synthesis of 6-substituted cis-2,8-dioxabicyclo[3.3.0]octan-3-ones is described. The pivotal step coupling a tertiary radical generated directly from alcohol with 3-chloro-5-alkoxybutenolide. This strategy applied toward scalable 14-15 syntheses three rearranged spongian diterpenoids: cheloviolenes and B dendrillolide C.

A highly efficient I2-promoted formal [4 + 2] cycloaddition has been developed for the synthesis of 2-acylquinolines from methyl ketones and arylamines using 1,4-dithane-2,5-diol as an ethylene surrogate. Moreover, investigation mechanism suggested that this reaction occurred via iodination/Kornblum oxidation/Povarov/aromatization sequence. It is noteworthy arylamine substrate also played important role in promoting reaction.

The development of a convergent fragment coupling strategy for the enantioselective total syntheses group rearranged spongian diterpenoids that harbor cis-2,8-dioxabicyclo[3.3.0]octan-3-one unit is described. key bond disconnection relies on late-stage between tertiary carbon radical and an electron-deficient alkene to unite two ring systems form new stereocenters, one which quaternary, in stereoselective efficient manner. This applied toward scalable 14–15 step three diterpenoids,...

We report an I2/FeCl3-co-promoted formal [2 + 2+1] annulation of aryl methyl ketones, 2-aminobenzyl alcohols, and p-toluenesulfonylmethyl isocyanide (TosMIC) by neighboring group (-CH2OH) assistance. This is a novel example using the Van Leusen reagent as unique C1N1 "two-atom synthon" in synthesis imidazoles. Preliminary mechanism studies showed that TsCH2NH2 might be key intermediate this reaction. Furthermore, reaction not only unlocks strategy for imidazole synthesis, but also exploits...

Background Applications involving biomolecules, such as enzymes, antibodies, and other proteins well whole cells, are often hampered by their unstable nature at extremely high temperature in organic solvents. Methodology/Principal Findings We constructed enzyme-NPG biocomposites assembling various enzymes onto the surface of nanoporous gold (NPG), which showed much enhanced biocatalytic performance stability. Various with different molecular sizes were successfully tethered NPG, loadings...

The addition of tertiary carbon radicals generated by an Ir-catalyzed visible-light photocatalyst to electron-deficient 1,3-dienes proceeds in good yields append a δ-substituted β,γ-unsaturated carbonyl fragment alcohol or carboxylic acid precursor and construct new quaternary center.

A novel iodine-promoted oxidative cross-coupling/cyclization of 2-(pyridin-2-yl)acetate derivatives and methyl ketones via the cleavage multiple Csp3-H bonds has been developed, which also achieved efficient a C-C bond in derivatives. This protocol represents an elegant molecular fragment assembly diverse 3-(pyridin-2-yl)indolizines formal [3 + 1 1] annulation. Notably, pyridine serve two pivotal roles to provide fragments construct 3-(pyridin-2-yl)indolizine skeletons, rather than single...

An I₂-promoted formal [3+2] cycloaddition for access to oxazoles has been demonstrated. The salient feature of this approach is unconventional 2,5-disubstituted oxazole formation from isocyanides and ketones rather than 4,5-substituted oxazoline.

An efficient I2/CuCl2-promoted one-pot three-component strategy for the construction of 1,2,3-thiadiazoles from aliphatic- or aromatic-substituted methyl ketones, p-toluenesulfonyl hydrazide, and potassium thiocyanate has been developed. Simple commercially available starting materials, a broad substrate scope, excellent functional group tolerability make this practical applications. Furthermore, 1,2,3-thiadiazole synthesis was realized by using as an odorless sulfur source.

The first synthesis of arylquinazolinones has been disclosed via the consecutive oxidative cyclization/ring-opening anilines and methyl ketones. This transformation is characterized by splitting ketone as acyl C1 sources through C(CO)–C(sp3) bond cleavage, using DMSO a source C–S which expands use ketones valuable building blocks enriches library preparation quinazolinones. Moreover, preliminary mechanistic studies indicate that this multicomponent reaction underwent sequence.

A novel and efficient multicomponent cyclization of methyl ketones, cyanamides, arylamines for the synthesizing 2,4-diamino-1,3,5-triazines via consecutive formation four C-N bonds is reported. This reaction characterized by employment two molecules cyanamide double C(sp3)-H amination avoiding complicated prepreparation substrates expanding substrate scope. Furthermore, this strategy provides a new approach generating diverse with broad scope under mild conditions.

An intramolecular pyrone Diels–Alder reaction–elimination retro-Diels–Alder cascade of a vinyl sulfone was used in the synthesis cavicularin, molecule possessing conformational chirality. The substitution pattern allowed for regiocontrol event.

The iodine-catalyzed catalytic formal [3 + 3 1] cycloaddition for the preparation of a seven-membered O-heterocyclic ring is presented, which an achievement methyl and carbonyl group reactivity 3-methyl-5-pyrazolones to forge Csp3-O bond. This novel protocol provides straightforward efficient access structurally diverse fused O-heterocycles through iodination/Kornblum oxidation/oxidative coupling/C-O bond formation cascade reaction. approach demonstrates unprecedented concurrent realization...

A N–H/α,β-C(sp3)-trifunctionalization of l-proline, proceeding through an iodine-promoted consecutive decarboxylation/ring-opening/dicyclization process, is achieved. This strategy affords structurally diverse fused N-heterocycles in good yields with a wide substrate scope. Preliminary mechanistic studies indicate that catabolism l-proline might be involved this cascade reaction and the situ generated intermediate 4-aminobutanal was identified as key intermediate. Notably, domino enriches...

Mesoionic carbene–iridium complex 1a has been investigated in the hydrogen isotope exchange (HIE) reaction of anilines. By employing 1 mol % as catalyst, anilines were selectively deuterated at ortho-position with high deuteration levels. High ortho-selectivity was observed for various competing directing groups, which is contrast catalytic results Kerr's catalysts.

A novel I2-mediated Povarov reaction of arylacetylenes and anilines for the synthesis 2,4-substituted quinolines has been developed, in which arylacetylene first acts as both a diene precursor dienophile. This work further develops to expand types precursors. Preliminary mechanistic studies indicate that I2/DMSO system realized oxidative carbonylation C(sp)–H then undergoes [4 + 2] cycloaddition reaction.

A unique strategy toward the synthesis of polysubstituted indolizines has been developed. When 2-pyridinyl-2-(2'-bromoallyl)-1-carboxylates were treated with Cs2CO3, starting material went through a methylenecyclopropane ring formation/opening cascade, and corresponding obtained in moderate to good yield as single regioisomer.