Diyne Systems Research Articles

Kaskadenreaktionen von aryl‐substituierten terminalen Alkinen unter Beteiligung von in situ erzeugten α‐Imino‐Goldcarbenen

AbstractWir berichten über eine effiziente, hochselektive und divergente Synthesemethode zur Herstellung von 2‐substituierten Indolen und aryl‐anellierten Carbazolen über die intermolekulare Erzeugung von α‐Imino‐Goldcarbenen aus terminalen Alkinen oder Diinen in Kombination mit Sulfiliminen. Wichtig ist, dass die Tandemreaktion durch eine intermolekulare Goldcarbenbildung/C−H‐ Anellierung, gefolgt von der Aktivierung eines zweiten Alkins, die zu einer 6‐endo‐dig‐Zyklisierung führt, abläuft, was sich deutlich von früheren Ansätzen der dualen Aktivierung oder 1,6‐Carbenverschiebung für Diin‐Systeme unterscheidet. Im Falle von ortho‐Alkinylanilin als Ausgangsmaterial wurde eine unerwartete regioselektive Bildung der Indolkomponente über den intermolekularen Weg anstelle einer intramolekularen Hydroaminierung entdeckt. Diese Reaktivität ebnete den Weg für eine Eintopfsynthese des 11H‐Indolo‐[3,2‐c]‐Chinolin‐Gerüsts, indem das gebildete Aminoindol für eine anschließende Pictet–Spengler‐Reaktion mit Aldehyden genutzt wurde. Die photophysikalischen Eigenschaften der Carbazole zeigten eine gute violett‐blaue Emission mit Quantenausbeuten von bis zu 40 %.

Cascade Reactions of Aryl-Substituted Terminal Alkynes Involving in Situ-Generated α-Imino Gold Carbenes.

An efficient, highly selective and divergent synthetic method to construct 2-substituted indoles and aryl-annulated carbazoles via the intermolecular generation of α-imino gold carbenes from terminal alkynes or diynes in combination with sulfilimines is disclosed. Importantly, the tandem reaction is proposed to proceed through an intermolecular gold carbene generation/C-H annulation followed by the activation of a second alkyne leading to 6-endo-dig cyclization, which is significantly different from previous dual activation or 1,6-carbene shift approaches for diyne systems. In the case of ortho-alkynylaniline as starting material, an unexpected regioselective formation of the indole moiety via the intermolecular path, instead of intramolecular hydroamination was discovered. This reactivity paved the way for a one-pot synthesis of the 11H-indolo [3,2-c] quinoline scaffold by exploiting the formed amino indole for a subsequent Pictet-Spengler reaction with aldehydes. The photophysical properties of the carbazoles indicated good violet-blue emission with quantum yields up to 40 %.

Gold Catalysis: 2,3‐ or 1,4‐Addition to Butadiynes

AbstractIn the past, numerous impressive methodologies have been developed in homogeneous gold catalysis, typically using alkynes, allenes, or different non‐conjugated diyne systems as starting materials. While there are applications catalyzed by other transition metals, the use of 1,3‐butadiyne derivatives has been largely neglected in gold catalysis. In this work we present an efficient gold‐catalyzed method focusing on the functionalization of this specific type of diynes. The starting materials can be synthesized via simple Glaser Coupling, starting from cheap, highly variable, terminal alkynes. These homocoupling products, which are often observed as undesirable side‐products in Sonogashira reactions, can be converted into versatile 1,3‐butadiene derivatives in alcohol as a solvent and nucleophile under mild conditions. The possible field of application of the 1,3‐butadiene derivatives known from the literature is very broad and ranges from a use as transistor or OLED material to a use as an enzyme inhibitor. The approach presented here offers an attractive and highly effective way to versatile functionalized 1,3‐butadiene derivatives.magnified image

ChemInform Abstract: Gold‐Catalyzed Carbenoid Transfer Reactions of Diynes — Pinacol Rearrangement versus Retro‐Buchner Reaction.

ChemInformVolume 46, Issue 30 Isocyclic Compounds ChemInform Abstract: Gold-Catalyzed Carbenoid Transfer Reactions of Diynes — Pinacol Rearrangement versus Retro-Buchner Reaction. Tobias Lauterbach, Tobias Lauterbach Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorTakafumi Higuchi, Takafumi Higuchi Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorMatthias W. Hussong, Matthias W. Hussong Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorMatthias Rudolph, Matthias Rudolph Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorFrank Rominger, Frank Rominger Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorKazushi Mashima, Kazushi Mashima Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorA. Stephen K. Hashmi, A. Stephen K. Hashmi Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this author Tobias Lauterbach, Tobias Lauterbach Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorTakafumi Higuchi, Takafumi Higuchi Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorMatthias W. Hussong, Matthias W. Hussong Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorMatthias Rudolph, Matthias Rudolph Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorFrank Rominger, Frank Rominger Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorKazushi Mashima, Kazushi Mashima Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this authorA. Stephen K. Hashmi, A. Stephen K. Hashmi Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, GermanySearch for more papers by this author First published: 14 July 2015 https://doi.org/10.1002/chin.201530127Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume46, Issue30July, 2015 RelatedInformation

Gold‐Catalyzed Carbenoid Transfer Reactions of Diynes – Pinacol Rearrangement versus Retro‐Buchner Reaction

AbstractAromatic diyne systems bearing one terminal propargylic acetate moiety and one tertiary propargylic alcohol subunit were converted in the presence of a gold catalyst. After an initial 1,2‐migration of the acetoxy group at the terminal alkyne, a gold carbenoid is formed which is then transferred onto the internal alkyne of the propargylic alcohol. This combination enables the use of propargylic acetates as precursors for a gold‐catalyzed pinacol‐type rearrangement. In the final pinacol‐like step the shift of an alkyl or aryl moiety onto an electrophilic gold carbenoid/cation terminates the reaction and 1‐naphthyl ketones are obtained as products. If electron‐rich aromatic backbones are used, a mechanistically interesting alternative pathway including a retro‐Buchner reaction is opened.magnified image

CO extrusion in homogeneous gold catalysis: reactivity of gold acyl species generated through water addition to gold vinylidenes.

Herein, we describe a new gold-catalyzed decarbonylative indene synthesis. Synergistic σ,π-activation of diyne substrates leads to gold vinylidene intermediates, which upon addition of water are transformed into gold acyl species, a type of organogold compound hitherto only scarcely reported. The latter are shown to undergo extrusion of CO, an elementary step completely unknown for homogeneous gold catalysis. By tuning the electronic and steric properties of the starting diyne systems, this new reactivity could be exploited for the synthesis of indene derivatives in high yields.

Dietary acetylenic oxylipin falcarinol differentially modulates GABAA receptors.

The dietary oxylipins falcarinol (1a) and falcarindiol (1b) trap thiols by direct nucleophilic addition to their diyne system, but despite this, only falcarinol (1a) is a reversible agonist of cannabinoid receptors, providing a rationale for comparing their activity also on other neuronal targets. Because GABAA receptors (GABAARs) are exquisitely sensitive to polyacetylenic oxylipins in terms of either potentiation (falcarindiol, 1b) or inhibition (oenanthotoxin, 2a), the activity of 1a was investigated on synaptic (α1β2γ2L) and extrasynaptic (α1β2δ and α1β2) subtypes of GABAARs. Falcarinol (1a) significantly enhanced the amplitude of currents mediated by α1β2γ2L receptors, but this effect was associated with a use-dependent block. Conversely, α1β2 receptors were inhibited without any sign of use-dependent block for the entire range of concentrations tested (1-10 μM). Interestingly, responses mediated by α1β2δ receptors, showing no or very little macroscopic desensitization, were strongly potentiated by 1a, exhibiting a fading reminiscent of macroscopic desensitization. When compared to the activity of falcarindiol (1b), falcarinol (1a) showed a higher affinity for GABAARs and, overall, a substantially different profile of pharmacological action. Taken together, the present data support the view that modulation of GABAARs might underlie the insecticidal and sedative activity of falcarinol (1a).

Dual Gold Catalysis: Synthesis of Polycyclic Compounds via CH Insertion of Gold Vinylidenes

New and interesting polycyclic compounds have been synthesized from non-conjugated diyne systems by dual gold catalysis. A quaternary carbon center in the backbone and the accompanying Thorpe-Ingold effect enabled the unprecedented insertion of sp(3) and sp(2) CH bonds that for the first time were incorporated within the backbone of the diyne system and allowed the construction of complex polycyclic carbon scaffolds inaccessible by previous approaches in which the CH bonds for the insertion were situated at the other end of the alkyne.

ChemInform Abstract: Rational Design of a Palladium‐Catalyzed Csp—Csp Cross‐Coupling Reaction Inspired by Kinetic Studies.

AbstractThe highly selective, efficient, simple, and mild method affords a series of synthetically important diyne systems.

Mechanistic Switch in Dual Gold Catalysis of Diynes: C(sp3)–H Activation through Bifurcation—Vinylidene versus Carbene Pathways

The other side of the mountain: Changing the framework of diyne systems opens up new cyclization modes for dual gold catalysis. Instead of a 5-endo cyclization and gold vinylidenes a 6-endo cyclization gives rise to gold-stabilized carbenes as key intermediates for selective C-H insertions.

Synthesis, Properties and Redox Behavior of Ene–Diyne Scaffolds Bearing 1‐ and 2‐Azulenyl Groups at the Periphery

AbstractEne–diyne systems possessing 1‐ and 2‐azulenyl groups at the periphery were prepared by palladium‐catalyzed cross‐coupling reaction of 1‐ and 2‐ethynylazulenes with 9‐dibromomethylene‐9H‐fluorene and 9,10‐bis(dibromomethylene)‐9,10‐dihydroanthracene or 2‐iodoazulene with 9,10‐bis(diethynylmethylene)‐9,10‐dihydroanthracene under Sonogashira–Hagihara conditions. The redox behavior of the ene–diyne compounds was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Moreover, a significant color change of the ene–diyne derivatives was observed with visible spectroscopy under electrochemical reduction conditions.

Synthesis and [2+2] Cycloaddition with Tetracyanoethylene of Ene–Diyne Scaffolds Bearing Ferrocenes at the Periphery

AbstractThe ene–diyne systems 1 and 2, possessing ferrocenyl groups at the periphery, were prepared by a simple one‐pot Sonogashira–Hagihara coupling reaction of ethynylferrocene with 9‐dibromomethylene‐9H‐fluorene (4) and 9,10‐bis(dibromomethylene)‐9,10‐dihydroanthracene (5). Ene–diyne 1 reacted with tetracyanoethylene (TCNE) in a formal [2+2] cycloaddition reaction, followed by ring opening of the initially formed [2+2] cycloadduct, cyclobutene, to afford the corresponding 1,1,4,4‐tetracyanobutadiene (TCBD) derivative 6 in good yield. The redox behavior of the ene–diyne compounds 1 and 2, and the TCBD derivative 6 was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), which revealed their electrochemical oxidation properties with multi‐electron transfer depending on the number of ferrocene units in the molecule, in addition to the two‐electron reduction of the TCBD moiety in the case of TCBD derivative 6. Moreover, a significant color change was observed by visible spectroscopy under electrochemical oxidation conditions and under reduction conditions in the case of TCBD derivative 6.

Synthesis of 1,3-diynes via detelluration of bis(ethynyl)tellurides

The synthesis of symmetric conjugated diyne systems with electron-withdrawing or electron-donating substituents via a palladium-catalyzed detelluration of bis(arylethynyl)tellurides and bis(alkylethynyl)tellurides is described. This procedure is effected under atmospheric conditions in DMF using Pd(OAc)2 as a catalyst and AgOAc as an additive in the presence of triethylamine. This route offers efficient access to conjugated diyne systems in short reaction time. X-ray crystallographic structure and solid-state conformation of bis(p-tolylethynyl)telluride show a supramolecular chain aligned along the b axis, sustained by C-H...π interactions.

Synthesis and redox behavior of ene–diyne scaffolds that bear ferrocenes at the periphery

The ene–diyne systems 1 and 2 possessing ferrocenyl groups at the periphery were prepared by the simple one-pot Sonogashira–Hagihara coupling reaction of ethynylferrocene with 9-dibromomethylene-9 H-fluorene ( 4) and 9,10-bis(dibromomethylene)-9,10-dihydroanthracene ( 5). The novel ferrocene-substituted ene–diyne compounds exhibited amphoteric redox behavior with a reversible one-stage electrochemical oxidation upon cyclic voltammetry.

Synthesis of the Bicyclic [7.3.0] Enediyne System of the Maduropeptin Chromophore: Remarkable Atropisomerism of Ansamacrolactam and Isomerization of the C4—C13 Double Bond.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Total synthesis of ichthyotoxic macrolides from the skin of the marine mollusk Aplysia depilans

A convergent pathway is described for the synthesis of natural aplyolides A–E (1–5), ichthyotoxic macrolides isolated from the skin of the marine mollusk Aplysia depilans. Aplyolide A (1) was prepared using ethyl (S)-lactate as chiral source. Key diols for the preparation of aplyolides B–E (2–5) were obtained stereoselectively by Sharpless asymmetric dihydroxylation of eneyne precursors. An improved procedure, based on cesium carbonate as base for alkynide preparation, was used in key steps of the synthesis involving coupling reactions between copper (I) alkynides and propargylic halides for the formation of skipped diyne systems. Finally, the crucial step of macrocyclization was accomplished using the Yamaguchi methodology.

Synthesis of the Bicyclic [7.3.0] Enediyne System of the Maduropeptin Chromophore: Remarkable Atropisomerism of Ansamacrolactam and Isomerization of the C4-C13 Double Bond

A nine-membered diyne system of the maduropeptin chromophore was constructed for the first time using Nozaki-Hiyama-Kishi reaction. Unexpected atropisomerism of deoxyansamacrolactam and cis/trans isomerization of the exo-double bond of the chromophore were observed.

Reactions of Diacetylene Ligands with Trinuclear Clusters. 3. Cyclization of Diynes with β-Amino Moieties on the Metal Core of [H2Os3(CO)10

Reactions of [H2Os3(CO)10] with the substituted diynes R-C2-C2-R' (1, R = Ph, R' = CH2NHPh; 2, R = Ph, R' = CH2NHCH2Ph; 3, R = R' = CH2NHPh) afford the clusters [HOs3(CO)10(L)] (L = {-1:2-PhCH2C(H)=C-C(H)=C-NPh} (4), {-1:2-PhCH2C(H)=C-C(H)=C-NCH2Ph} (5), and {-1:1-CH3CC=C-C(H)=C(H)-NPh} (6), which have been characterized by single-crystal X-ray diffraction analyses as well as by various spectroscopic methods. In clusters 4-6, the starting diynes 1-3 have been rearranged to form substituted pyrrolyl rings which bridge two osmium atoms in 1:2- (4, 5) or 1:1- (6) coordination modes depending on the nature of substituents in 1-3. A possible reaction pathway for the diyne cyclization reactions that yield 4-6 involves initial transfer of a hydride onto a coordinated diyne followed by a series of 1,3-shifts and subsequent nucleophilic attack of the nitrogen on the third carbon atom of the diyne system to afford the five-membered pyrrolyl ring. Cluster 6 and its previously characterized furanyl analogue [HOs3(CO)10{-1:1-(OCHCHCC)-C-CH3)}] (7) undergo facile thermal transformation accompanied by the loss of a CO ligand to give the clusters [HOs3(CO)9{3,3-CH3CC=C-C(H)=C(H)-NPh}] (8) and [HOs3(CO)9{3,3-(OCH=CHC=CCCH3)}] (9). In both 8 and 9, single-crystal X-ray analysis revealed the presence of pentagonal pyramid cluster cores containing three osmium and three carbon atoms. (Less)

ChemInform Abstract: Efficient Route to the Nine‐Membered Cyclic Diyne System: Tuning of the Extremely Facile Cope Rearrangement of 1,5‐Diyne.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Efficient Route to the Nine-Membered Cyclic Diyne System: Tuning of the Extremely Facile Cope Rearrangement of 1,5-Diyne

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEfficient Route to the Nine-Membered Cyclic Diyne System: Tuning of the Extremely Facile Cope Rearrangement of 1,5-DiyneKyoichiro Iida and Masahiro HiramaCite this: J. Am. Chem. Soc. 1994, 116, 22, 10310–10311Publication Date (Print):November 1, 1994Publication History Published online1 May 2002Published inissue 1 November 1994https://doi.org/10.1021/ja00101a065RIGHTS & PERMISSIONSArticle Views589Altmetric-Citations68LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (256 KB) Get e-AlertsSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts