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π-Conjugated donor–acceptor (D–A) polymers containing electron withdrawing non-S-oxidized 4H-1,2,6-thiadiazines and electron donating (het)aryl-substituted indacenodithiophenes (IDTs) were prepared and used in organic solar cell (OSC) devices with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the fullerene acceptor. The non-S-oxidized 4H-1,2,6-thiadiazine containing polymers were wide bandgap absorbers (Eoptg 1.80–1.95 eV) with low-lying highest occupied molecular orbital energy levels (EHOMO −5.5 to −6.1 eV) affording high open circuit voltages (Vocs 0.82–0.96 V) for polymer:fullerene bulk heterojunction (BHJ) OSCs. Owing to enhanced short circuit currents (Jscs) and fill factors (FFs), the 1,2,6-thiadiazin-4(H)-one-based polymers had significantly higher performances (up to 3.83%) vs. the N-(perfluorophenyl)-1,2,6-thiadiazin-4(H)-imine based-polymers (up to 1.37%). 6 14 3658 3667

Tin reduction of 3,4,4,5-tetrachloro-4H-1,2,6-thiadiazine afforded perchloro-9-thia-1,5,8,10-tetraazaspiro[5.5]undeca-1,4,7,10-tetraene (10%) and 3,5-dichloro-4H-1,2,6-thiadiazine-4-thione (27%), the structures of which were supported by single crystal X-ray crystallography. Treating the tetrachlorothiadiazine with Ph3P (1 equiv.) afforded the corresponding spirocycle in a useful 66% yield, the degradation of which with BnEt3NCl (0.5 equiv.) afforded densely functionalized 4,5,6-trichloropyrimidine-2-carbonitrile in 81% yield. Rational mechanisms for the formation of products are proposed. © 2017 Elsevier Ltd 58 26 2618 2621

A three-step synthesis of 3?,5?-dichloro-1H-spiro(quinazo-line-2,4?-[1,2,6]thiadiazin)-4(3H)-ones starting from 3,4,4,5-tetra-chloro-4H-1,2,6-thiadiazine is presented. The latter reacts with 2-aminobenzonitriles to give 2-[(3,5-dichloro-4H-1,2,6-thiadiazin-4-ylid-ene)amino]benzonitriles, which affords, after hydration, the respective benzamides. Upon heating at reflux in EtOH or HFIP, the benzamides intramolecularly cyclize onto the thiadiazine C4 position to give 3?,5?-dichloro-1H-spiro(quinazoline-2,4?-[1,2,6]thiadiazin)-4(3H)-ones. Single crystal X-ray crystallography supports the structure of two analogues. The chloride displacement of these new spiroquinazolinones was demonstrated by Stille coupling, and by reaction with methoxide to afford both the mono and bis-methoxy derivatives. 2019 31-32 5462 5474

4,6-Dichloro-2-(methylthio)pyrimidine (7) was converted to 4-chloro-6-methoxy-2-(methylthio)pyrimidine (15) and 4,6-dimethoxy-2-(methylthio)pyrimidine (14). Chlorination of the latter with N-chlorosuccinimide (NCS) affords 5-chloro-4,6-dimethoxy-2-(methylthio)pyrimidine (16) in 56% yield. Both methylthiopyrimidines 15 and 14 were converted in two steps to 4-chloro-6-methoxypyrimidine-2-carbonitrile (13) and 4,6-dimethoxypyrimidine-2-carbonitrile (12), respectively, after oxidation to sulfones and displacement of the sulfinate group with KCN. 4,6-Dimethoxypyrimidine-2-carbonitrile (12) was chlorinated with NCS to give 5-chloro-4,6-dimethoxypyrimidine-2-carbonitrile (10) in 53% yield. All new compounds were fully characterized.

Stille coupling of 3,5-bis(5-bromothien-2-yl)-4H-1,2,6-thiadiazin-4-one (10) with 2-(tri-n-butylstannyl)thiazole and Pd(Ph3P)2Cl2 in PhMe, at ca. 110 °C, for 2 h, gave 3,5-bis[5-(thiazol-2-yl)thien-2-yl]-4H-1,2,6-thiadiazin-4-one (9) in 81% yield. The latter is evaluated for its electronic properties.

A near-quantitative acid and/or thermal mediated ring contraction of 3′,5′-diarylspiro(benzo[d][1,3]dioxole-2,4′-[1,2,6]thiadiazines) affords 3-aryl-4-(2-arylbenzo[d][1,3]dioxol-2-yl)-1,2,5-thiadiazoles. The reaction scope was studied providing 11 examples of this ring contraction. A double Wagner-Meerwein reaction mechanism is proposed. © 2016 American Chemical Society. 18 16 4056 4059 Cited By :1

The reactivity of 3,5-dichloro-4H-1,2,6-thiadiazine 4,4-ketals towards nucleophilic substitution or palladium-catalyzed C–C coupling at the C-3/5 positions led to seven new 3,5-disubstituted 4H-1,2,6-thiadiazine ethylene glycol 4,4-ketals and seven 3,5-disubstituted 4H-1,2,6-thiadiazine catechol 4,4-ketals in 83–98% yields. Furthermore, 3,5-diphenyl-4H-1,2,6-thiadiazine ethylene glycol and catechol 4,4-ketals were successfully hydrolysed in conc. H2SO4at 20 °C to afford 3,5-diphenyl-4H-1,2,6-thiadiazin-4-one in 74% and 89% yields. © 2016 Elsevier Ltd 57 30 3307 3310 Cited By :2

Stille coupling of 5,5′-dichloro-4H,4′H-[3,3′-bi(1,2,6-thiadiazine)]-4,4′-dione (8) with 9-decyl-3-[5-(tributylstannyl)thien-2-yl]-9H-carbazole and Pd(Ph3P)2Cl2 in PhMe, at ca. 110 °C, for 2 h, gave 5,5′-bis[5-(9-decyl-9H-carbazol-3-yl)thien-2-yl]-4H,4′H-[3,3′-bi(1,2,6-thiadiazine)]-4,4′-dione (7) in 51% yield. The latter is investigated as an oligomer donor for organic photovoltaics. 2018 1

3,4,4,5-Tetrachloro-4H-1,2,6-thiadiazine was reacted with BnEt3NCl (10 mol%) to give perchloro-9-thia-1,5,8,10-tetraazaspiro[5.5]undeca-1,4,7,10-tetraene (up to 18% yield), 4,5,6-trichloropyrimidine-2-carbonitrile (up to 44% yield) and four minor side products: 2,7-dichlorothiazolo[5,4-d]pyrimidine-5-carbonitrile, 2-(4-chloro-6H-thiazolo[5,4-c][1,2,6]thia-diazin-6-ylidene)malononitrile, 4,8-dichloropyrrolo[2′,1′:2,3]imidazo[4,5-c][1,2,6]thiadiazine-6,7-dicarbonitrile and 4,7-dichloro-[1,2,6]thiadiazino[3,4-b]thiazolo[5,4-e][1,4]diazepin-9(10H)-one. Single crystal X-ray studies support the structures of the minor products. Tentative rationale for the formation of these minor products and the synthesis of 8-bromo-4-chloropyrrolo[2′,1′:2,3]imidazo[4,5-c][1,2,6]thiadiazine-6,7-dicarbonitrile are presented. 59 40 3589 3593

We demonstrate for the first time that 4H-1,2,6-thiadiazin-4-one (TDZ) can function as a chemotype for the design of ATP-competitive kinase inhibitors. Using insights from a co-crystal structure of a 3,5-bis(arylamino)-4H-1,2,6-thiadiazin-4-one bound to calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), several analogues were identified with micromolar activity through targeted displacement of bound water molecules in the active site. Since the TDZ analogues showed reduced promiscuity compared to their 2,4-dianilinopyrimidine counter parts, they represent starting points for development of highly selective kinase inhibitors. 23 5

The Buchwald-Hartwig Pd-catalyzed C-N coupling reaction of 5-substituted 3-chloro-4H-1,2,6-thiadiazin-4-ones with primary (het)arylamines is described, affording twenty new 3,5-disubstituted 4H-1,2,6-thiadiazin-4-ones in 56–99% yield. The protocol enables the mild preparation of difficult to access 3,5-dianilino-1,2,6-4H-thiadiazin-4-ones. The reaction scope and limitations are discussed. 59 27 2653 2656

The optical, electrochemical, morphological and transport properties of a series of thiadiazinone (acceptor) and (thienyl)carbazoles (donor) containing π-extended donor-acceptor-donors (D-A-D) are presented. Systematic variations in the number of the thienyl units, the choice of branched or straight alkyl side chains and the use of a processing additive demonstrate their use as electron donors in bulk heterojunction solar cells blended with fullerene acceptors. The best power conversion efficiency (PCE) of 2.7% is achieved by adding to the D-A-D 3:fullerene blend a polydimethylsiloxane (PDMS) additive, that improves the morphology and doubles the hole mobility within the D-A-D:fullerene blend. © The Royal Society of Chemistry. 3 10 2358 2365 Cited By :7

Three 3,5-dichloro-4H-1,2,6-thiadiazines, which differ according to the electron withdrawing nature of their substituent at C-4: (a) 3,5-dichloro-4-methylene-4H-1,2,6-thiadiazine (5a), (b) 3,5-dichloro-4H-1,2,6-thiadiazin-4-one (5b) and (c) 2-(3,5-dichloro-4H-1,2,6-thiadiazin-4-ylidene)malononitrile (5c), are characterized using resonance Raman (RR), absorption (UV/vis) and photoluminescence (PL) spectroscopies. These weakly aromatic and electron-deficient heterocycles are potential components as acceptors in donor-acceptor systems for organic electronics. Experimental results, which include the synthesis, characterization and single crystal X-ray structure of 3,5-dichloro-4-methylene-4H-1,2,6-thiadiazine (5a), combined with theoretical calculations of their orbitals and vibrational frequencies, provide an understanding of the optical properties, on the basis of molecular geometry and electron distribution. © The Royal Society of Chemistry 2015. 5 24 18471 18481 Cited By :3

Linear (co)polymers and dimethacrylate-end-linked polymer networks of methyl methacrylate with 2-(dimethylamino)ethyl methacrylate, cleavable in the middle of the polymer chain, either under thermolysis or alkaline hydrolysis conditions, were prepared via atom transfer radical polymerization (ATRP) using a specially designed bifunctional degradable initiator. This initiator was 2,6-pyridinediethanol di(2-bromo-2-methyl propanoate) (PyDEDBrMeP), bearing two 2-(pyridin-2-yl)ethyl ester moieties, known for their thermal and hydrolytic (alkaline conditions) lability. As a control, a more stable bifunctional ATRP initiator, 2,6-pyridinedimethanol di(2-bromo-2-methyl propanoate) (PyDMDBrMeP), was also synthesized together with the corresponding linear polymers and polymer networks prepared from it. Thermal or hydrolytic treatment of the polymers prepared using PyDEDBrMeP led to a reduction in the molecular weights of the linear polymers by a factor of two, and to the conversion of the polymer networks to soluble branched (star) structures, consistent with the expected cleavage of the initiator residue located in the middle of the polymer chain. Thermal treatment of the polymers prepared using PyDMDBrMeP did not affect their molecular weight due to the thermal stability of the (pyridin-2-yl)methyl ester group, while treatment under alkaline hydrolysis conditions resulted in complete cleavage, similar to the PyDEDBrMeP-prepared polymers. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2342–2355. © 2017 Wiley Periodicals, Inc. 55 14 2342 2355 Cited By :1

Colloidal polyvinylpyrrolidone-stabilized Pd nanoparticles were embedded within 1,2-bis(2-iodoethoxy)ethane (BIEE)-crosslinked poly(2-dimethylamino)ethyl methacrylate homopolymer networks with defined structural characteristics. In the presented synthetic approach, the crosslinking step is realised in ambient conditions, thus avoiding nanoparticle agglomeration phenomena. These 3D polymer-based nanocomposite networks were evaluated as heterogeneous catalysts for Heck, Suzuki-Miyaura and Sonogashira coupling reactions. High catalytic activity and reusability was demonstrated in Heck reactions, substrate-specific outcomes were observed in Sonogashira couplings, while poor reactivity was observed in Suzuki-Miyaura couplings. The existing diversity in material structure and composition allows for further improvements leading to highly stable and robust 3D polymer-based nanocomposite heterogeneous catalysts that could find use in a wide range of transition metal-catalysed organic reactions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1 2635 2641 2635-2641

Ring transformation of readily prepared (4-chloro-5H-1,2,3-dithiazol-5- ylidene)acetonitriles afford 3-haloisothiazole-5-carbonitriles in good to excellent yields. The transformation can be mediated using HBr (g), HCl (g) or BnEt3NCl. Mechanisms for the transformations are discussed, together with rationalizations for the formation of side products. Furthermore, single crystal X-ray structures are provided for (Z)-2-(4-chloro-5H-1,2,3-dithiazol-5- ylidene)acetonitrile and (E)-2-bromo-2-(4-chloro-5H-1,2,3-dithiazol-5-ylidene) acetonitrile confirming the stereochemistry of the exocyclic ethene bond. © 2014 The Royal Society of Chemistry. 4 15 7735 7748 Cited By :6