A Novel Spiro[acridine‐9,9′‐fluorene] Derivatives Containing Phenanthroimidazole Moiety for Deep‐Blue OLED Application

Typical π–π stacking and aggregation‐caused quenching could be suppressed in the film‐state by the spiro conformation molecular design in the field of organic light‐emitting diodes (OLEDs). Herein, a novel deep‐blue fluorescent material with spiro conformation, 1‐(4‐(tert ‐butyl)phenyl)‐2‐(4‐(10‐phenyl‐10H ‐spiro[acridine‐9,9′‐fluoren]‐2‐yl)phenyl)‐1H ‐phenanthro[9,10‐d ]imidazole ( SAF‐BPI ), was designed and synthesized. The compound consists of spiro‐acridine‐fluorene (SAF) as donor part and phenanthroimidazole (BPI) as acceptor part. Owing to the rigid SAF skeleton, this compound exhibits a high thermal stability with a glass transition temperature (T _g) of 198 °C. The compound exhibits bipolar transporting characteristics demonstrated by the single‐carrier devices. The non‐doped OLEDs based on the SAF‐BPI as the emitting layer shows maximum emission at 448 nm, maximum luminance of 2122 cd m⁻², maximum current efficiency (CE) of 3.97 cd A⁻¹, and a maximum power efficiency of 2.08 lm W⁻¹. The chromaticity coordinate is stable at (0.15, 0.10) at the voltage of 7–11 V. The device shows a slow efficiency roll‐off with CE of 3.35 and 2.85 cd A⁻¹ at 100 and 1000 cd m⁻², respectively.     

Synthesis and characterization of aromatic cyclolinear phosphazene polyetherketones containing bis‐Spiro‐substituted cyclotriphosphazene unit

A novel monomer, 2,2‐bis‐(4′‐fluorobenzoylphenoxy)‐4,4,6,6‐bis[spiro‐(2′,2″‐dioxy‐1′, 1′‐biphenylyl)] cyclotriphosphazene, was synthesized and polymerized with 4,4′‐difluorobenzophenone as a comonomer and 4,4′‐isopropylidenediphenol or 4,4′‐(hexafluoroisopropylidene) diphenol in N,N‐dimethylacetamide at 162 °C for 4 h to give two series of aromatic cyclolinear phosphazene polyetherketones containing bis‐spiro‐substituted cyclotriphosphazene groups. The structure of the monomer was confirmed by ¹H, ¹³C, and ³¹P NMR. The effect of the incorporation of the bis‐spiro‐substituted cyclotriphosphazene group on the thermal properties of these polymers was investigated by DSC and thermogravimetric analysis. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2993–2997, 2001     

Synthesis of phenoxy‐substituted spiro‐ansa phosphazene derivatives

In this study, reactions of 2,4,4,6,6‐pentachloro‐2‐(2,4,6‐trimethylphenoxy)cyclo‐2λ⁵,4λ⁵,6λ⁵‐triphosphazatriene ( 1 ) and 2,4,4,6,6‐pentachloro‐2‐(2,4,6‐tritertbutylphenoxy)cyclo‐2λ⁵,4λ⁵,6λ⁵‐triphosphazatriene ( 2 ) with 2,2′‐dihydroxybiphenyl ( 3 ) in acetone in the presence of potassium carbonate have been investigated. Mono ansa ( 4 ) and spiro‐ansa ( 5 ) derivatives were obtained from of 3 with 1 , while mono spiro ( 6 ) and mono ansa ( 7 ) derivatives were obtained from 2 . © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:372–375, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20322     

Polymerization of o‐quinodimethanes. III. Polymerization of o‐quinodimethanes bearing electron‐withdrawing groups formed in situ by thermal ring‐opening isomerization of corresponding benzocyclobutenes

The substituent effect on the radical polymerization of o‐quinodimethanes, generated by thermal isomerization of benzocyclobutenes, was investigated. Polymerizations of three benzocyclobutenes bearing electron‐withdrawing groups were studied, namely 1‐cyanobenzocyclobutene (1), 1‐chlorobenzocyclobutene (2), and 1‐bromobenzocyclobutene (3). While radical polymerizations of 2 and 3 did not afford any polymer, radical polymerization of 1 afforded n‐hexane‐insoluble polymer(M_n = 5000) in moderate yields at temperatures above 120°C. The structure of the obtained polymer was confirmed to be a ring‐opened polymer(4) by IR, ¹H‐, and ¹³C‐NMR. The yield of the polymer increased with an increase in the initiator concentration. The polymer yield reported in this paper is higher than those of benzocyclobutenes bearing electron‐donating groups, reported previously by the authors. The semi‐empirical molecular orbital calculation supported the contribution of ring‐opening polymerization of spiro‐compounds, rejecting the possibility of 1,4‐polymerization. Lastly, radical copolymerizations of 1 with various comonomers were also performed to obtain the corresponding copolymers. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1555–1563, 1999     

Convenient Synthesis of Spiro[benzo[d]pyrrolo[2,1‐b]thiazole‐3,2′‐indenes] Derivatives via Three‐Component Reaction

The three‐component reaction of N‐phenacylbenzothiazolium bromides, aromatic aldehydes and indane‐1,3‐dione in ethanol at room temperature in the presence of triethylamine as base afforded functionalized spiro[benzo[d]pyrrolo[2,1‐b]thiazole‐3,2′‐indenes] in good yields and with high diastereoselectivity. The ¹H NMR data and single crystal structure clearly indicated that the obtained spiro compounds predominately have one diastereoisomer.     

Synthesis,Modification, and Anticonvulsant Activity of 3′‐R1‐Spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′(7′H)‐diones Derivatives

Previously unknown 3′‐R¹‐5‐R²‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazoline]‐2,2′‐(7′H)‐diones and their N‐substituted analogues were obtained via reaction of 6‐R¹‐3‐(2‐aminophenyl)‐1,2,4‐triazin‐5‐ones with isatin and its substituted derivatives. It was shown that alkylation of 3′‐R¹‐5‐R²‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′‐(7′H)‐diones by N‐R³‐chloroacetamides or chloroacetonitrile in the presence of а base proceeds by N‐1 atom of isatin fragment. The spectral properties (¹H and ¹³C NMR spectra) of synthesized compounds were studied, and features of spectral patterns were discussed. The high‐effective anticonvulsant and radical scavenging agents among 3′‐R¹‐5‐R²‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′(7′H)‐diones and their N‐substituted derivatives were detected. It was shown that compounds 2.2 , 2.8 , and 3.1 exceed or compete the activity of the most widely used in modern neurology drug—lamotrigine on the pentylenetetrazole‐induced seizures model. The aforementioned fact may be considered as a reason for further profound study of synthesized compounds using other pathology models.     

Efficient Blue‐Colored Solid‐State Dye‐Sensitized Solar Cells: Enhanced Charge Collection by Using an in Situ Photoelectrochemically Generated Conducting Polymer Hole Conductor

A high power conversion efficiency (PCE) of 5.5 % was achieved by efficiently incorporating a diketopyrrolopyrrole‐based dye with a conducting polymer poly(3,4‐ethylenediothiophene) (PEDOT) hole‐transporting material (HTM) that was formed in situ, compared with a PCE of 2.9 % for small molecular spiro‐OMeTAD‐based solid‐state dye solar cells (sDSCs). The high PCE for PEDOT‐based sDSCs is mainly attributed to the significantly enhanced charge‐collection efficiency, as a result of the three‐order‐of‐magnitude higher hole conductivity (0.53 S cm^?1) compared with that of the widely used low molecular weight HTM spiro‐OMeTAD (3.5×10^?4 S cm^?1).     

Novel and one‐pot Synthesis of Tetrahydropyrrolo[1,2‐a]‐2‐Methylbenzothiazole‐3‐Spiro‐1′‐Cyclohexa‐2′,5′‐Dien‐4′‐one‐4,5‐Dicarboxylate Derivatives via a Three Component Reaction

The three component condensation reactions involving 2‐methylbenzothiazole or 2,5‐dimethylbenzothiazole, dialkyl acetylenedicarboxylate, and 2,6‐dimethyl phenol or 2,6‐di‐tert‐butylphenol constitute a novel and one‐pot synthesis of tetrahydropyrrolo[1,2‐a ]‐2‐methylbenzothiazoles‐3‐spiro‐1^′‐cyclohexa‐2^′,5^′‐dien‐4^′‐one‐4,5‐dicarboxylate derivatives in good yields. The reactions proceeded at room temperature without using any catalyst. This method is very useful to functionalize benzothiazole derivatives in a one‐pot operation.     

Synthetic and spectral studies of novel spiro {bicyclo[3,3,0]octene‐8,3′(2′H)‐indol}‐2′‐ones obtained from indol‐2,3‐diones

The present article reports our approach toward the synthesis of spiro compounds via indol‐2,3‐diones. Thus, reaction of indol‐2,3‐dione derivatives with a secondary cyclic amino acid, namely, (R)‐(−)‐thiazolidine‐4‐carboxylic acid, affords a thiazolo‐oxazolidinone as the main product. When the reaction is carried out in the presence of a dipolarophile, 1,3‐dipolar cycloaddition to the intermediate azomethine ylide leads to a novel spiro compound. The products have been characterized on the basis of spectral studies, and the geometry of the intermediate iminium compound has been optimized by use of the semiempirical molecular orbital method. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 381–384, 1999     

A Convenient 1,3‐Dipolar Cycloaddition Reaction for the Synthesis of Spirooxindoles and Some Other Spirocompounds Containing the 1,3,4‐Oxadiazole Moiety

A series of spiro[indoline‐3,2′‐[1,3,4]oxadiazol]‐2‐ones were prepared from the reaction of isatin derivatives and hydrazonoyl chlorides through the 1,3‐dipolar cycloaddition reaction. This method has some important aspects, such as mild reaction condition, easy purification, and high yield of products. Also, the synthesis of spiro[acenaphthylene‐1,2′‐[1,3,4]oxadiazol]‐2‐one and spiro[[1,3,4]oxadiazole‐2,9′‐phenanthren]‐10′‐one were studied under the same condition. The structures were confirmed spectroscopically (IR, ¹H‐ and ¹³C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this reaction is proposed.     

Long‐Lived Charge‐Transfer State Induced by Spin‐Orbit Charge Transfer Intersystem Crossing (SOCT‐ISC) in a Compact Spiro Electron Donor/Acceptor Dyad

We prepared conceptually novel, fully rigid, spiro compact electron donor (Rhodamine B, lactam form, RB)/acceptor (naphthalimide; NI) orthogonal dyad to attain the long‐lived triplet charge‐transfer (³CT) state, based on the electron spin control using spin‐orbit charge transfer intersystem crossing (SOCT‐ISC). Transient absorption (TA) spectra indicate the first charge separation (CS) takes place within 2.5 ps, subsequent SOCT‐ISC takes 8 ns to produce the ³NI* state. Then the slow secondary CS (125 ns) gives the long‐lived ³CT state (0.94 μs in deaerated n‐hexane) with high energy level (ca. 2.12 eV). The cascade photophysical processes of the dyad upon photoexcitation are summarized as ¹NI*→¹CT→³NI*→³CT. With time‐resolved electron paramagnetic resonance (TREPR) spectra, an EEEAAA electron‐spin polarization pattern was observed for the naphthalimide‐localized triplet state. Our spiro compact dyad structure and the electron spin‐control approach is different to previous methods for which invoking transition‐metal coordination or chromophores with intrinsic ISC ability is mandatory.     

Unexpected Spiroproducts from the Reaction of N‐Benzoylglycine with Ortho‐Formylbenzoic Acids −3,5′‐Dioxo‐2′‐Phenyl‐1,3‐Dihydrospiro[Indene‐2,4′‐[1,3]Oxazol]‐1‐yl Acetates: Establishments of Their Structure

This paper describes a method of preparation of new 3,5′‐dioxo‐2′‐phenyl‐1,3‐dihydrospiro[indene‐2,4′‐[1,3]oxazol]‐1‐yl acetate and its 5‐chloro‐ and bromoderivatives as products of interaction of N‐benzoylglycine (hippuric acid) with corresponding ortho‐formylbenzoic acids. The reaction carried out in acetic anhydride media in the presence of piperidine as catalyst. The novel spirocompounds were purified by column chromatography from multicomponent reaction mixtures. The composition of the spiro‐products was confirmed by C, H, N element analysis. The structure was established by IR, MS, ¹H‐ and ¹³C‐NMR analysis including COSY ¹H‐¹³C experiments.     

Iodine‐Catalyzed Synthesis of Spiro[1,3,4‐benzotriazepine‐2,3′‐indole]‐2′,5(1H,1′H)‐diones under Mild Conditions

The I₂‐catalyzed preparation of spiro[1,3,4‐benzotriazepine‐2,3′‐indole]‐2′,5(1H,1′H)‐diones from 2‐aminobenzohydrazide and isatins in MeCN at room temperature in good‐to‐excellent yields is described. The structure of 3 was corroborated spectroscopically (IR, ¹H‐ and ¹³C‐NMR, and EI‐MS data). A plausible mechanism for this type of reaction is proposed (Scheme 2).     

An Approach to the Synthesis of Spiro[indene‐pyridoisoquinoline] Derivatives via 1,4‐Dipolar Cycloaddition of Isoquinoline and Acetylene Esters,and (1,3‐Dihydro‐1,3‐dioxo‐2H‐inden‐2‐ylidene)malononitrile

A concise and efficient approach to the spiro‐tetrahydroisoquinoline derivatives has been developed by 1,4‐dipolar cycloaddition of zwitterions resulting from isoquinoline and acetylene esters and (1,3‐dihydro‐1,3‐dioxo‐2H‐inden‐2‐ylidene)malononitrile in MeCN at room temperature. The significance of this method lies in good yields and ease of product purification, and no inert atmosphere is required. The structures of the products were confirmed spectroscopically (IR, ¹H‐ and ¹³C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this reaction is proposed (Scheme).     

Amine‐Promoted One‐Pot,Multicomponent Route to Spiro‐Fused‐Pyran Derivatives in Aqueous Media

The primary amine‐promoted synthesis of spiro‐fused‐pyran derivatives via the three‐component reaction of ninhydrin, malononitrile, and cyclic 1,3‐diketo compounds is described. This new methodology affords the title compounds in high yields and short time, and with easy workup without chromatographic purification steps or extraction. All structures were confirmed by IR, ¹H‐ and ¹³C‐NMR spectroscopy, and mass spectroscopy. A plausible mechanism for this type of reaction is proposed (Scheme 2).     

2,6‐Diaryl‐4,4‐disubstituted 1,4‐dihydropyridines: Source for spiro heterocycles

Novel spiro heterocycles ( 5–12 ) were obtained by the cyclocondensation of 2,6‐diaryl‐4,4‐dimethoxycarbonyl‐/4‐cyano‐4‐ethoxycarbonyl‐1,4‐dihydropyridines( 3/4 ) with hydrazine hydrate, hydroxylamine hydrochloride, urea, and thiourea. All the compounds were characterized by IR, ¹H NMR, and ¹³C NMR spectral data.© 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:513–517, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10183     

Synthesis and chemistry of new spiro‐Δ1‐pyrazoline

In explorations of syntheses and chemistry of spiroheterocycles, we found that the reaction of 2‐diazopropane with (E)‐α‐arylidenepyrrolin‐2‐one, (E)‐α‐arylidene‐γ‐butyrolactone, and (E)‐arylidene‐N‐arylsuccinimide derivatives produced spiro‐Δ¹‐pyrazolines. The photolysis of Δ¹‐pyrazolines has led to cyclopropanes. The structures of the obtained adducts have been assigned by means of spectroscopic measurements. J. Heterocyclic Chem., (2011).     

Simplified synthesis of spiro‐bridged ladder‐type poly(p‐phenylene)

In this study, a simplified route to synthesize soluble, spiro‐bridged ladder‐type poly(p‐phenylene)s (spiro‐LPPP) was developed. The new, simplified synthesis route for spiro‐LPPP involves two reaction steps: a single‐stranded precursor polymer containing diaryloylbenzene building blocks was obtained by the Suzuki reaction, followed by a subsequent twofold cyclization cascade using methanesulfonic acid to form the target spiro‐LPPP. Spiro‐LPPP shows a well‐defined chemical structure, high molecular weight (M_n of 17,500 g/mol with a polydispersity index of 2.0), excellent thermal stability (5% weight loss at 370 °C), and good solubility in common organic solvents. Spiro‐LPPP emits blue light (λ_max,em = 455 nm) with the high solution PL quantum yield (94%). The spectral properties of spiro‐LPPP in the solid state are very similar to the solution properties, thus indicating a low degree of intermolecular aggregation. After annealing a thin film of spiro‐LPPP to 120 °C in air for 3 to 24 h, its emission spectrum is unchanged, reflecting excellent thermooxidative stability. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5137–5143, 2009     

Silicon‐Based Material with Spiro‐Annulated Fluorene/Triphenylamine as Host and Exciton‐Blocking Layer for Blue Electrophosphorescent Devices

A novel silicon‐based compound, 10‐phenyl‐2′‐(triphenylsilyl)‐10H‐spiro[acridine‐9,9′‐fluorene] (SSTF), with spiro structure has been designed, synthesized, and characterized. Its thermal, electronic absorption, and photoluminescence properties were studied. Its energy levels make it suitable as a host material or exciton‐blocking material in blue phosphorescent organic light‐emitting diodes (PhOLEDs). Accordingly, blue‐emitting devices with iridium(III) bis[(4,6‐difluorophenyl)‐pyridinato‐N,C²′]picolinate (FIrpic) as phosphorescent dopant have been fabricated and show high efficiency with low roll‐off. In particular, 44.0 cd A^?1 (41.3 lm W^?1) at 100 cd m^?2 and 41.9 cd A^?1 (32.9 lm W^?1) at 1000 cd m^?2 were achieved when SSTF was used as host material; 28.1 lm W^?1 at 100 cd m^?2 and 20.6 lm W^?1 at 1000 cd m^?2 were achieved when SSTF was used as exciton‐blocking layer. All of the results are superior to those of the reference devices and show the potential applicability and versatility of SSTF in blue PhOLEDs.     

Synthesis and characterization of novel (9H‐fluoren‐9‐ylamino) carbonylaminomethylphosphonic acid

The new α‐aminophosphonic acids are synthesized, reacting (9H‐fluoren‐9‐yl)urea with formaldehyde and phosphorus trichloride. (9H‐Fluoren‐9‐yl)urea was prepared from spiro(fluoren‐9,4′‐imidazolidine)‐2′,5′‐dione by alkaline hydrolysis with Ba(OH)₂. The structure of the title compounds was proved by means of IR, ¹H, ¹³C, and ³¹P NMR spectroscopy. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:719–722, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20500