Diastereoisomeric dinuclear ruthenium complexes of 2,5-di(2-pyridyl)thiazolo[5,4-d]thiazole

The first metal complexes of 2,5-di(2-pyridyl)thiazolo[5,4-d]thiazole (5) are described. X-Ray crystal structures are reported for the free ligand 5, a dinuclear copper complex 6 and the two diastereoisomers, 7meso and 7rac, of the dinuclear bis(2,2'-bipyridine)ruthenium complex. The two diastereoisomers of 7 and the 4,4'-dimethyl-2,2'-bipyridine analogue 8 are readily separated by cation exchange chromatography. 1H NMR and visible absorption spectra and electrochemical data for the four dinuclear ruthenium complexes reveal that these have relatively small HOMO-LUMO energy gaps and exhibit relatively weak metal-metal interactions.     

A Stable Luminescent MOF Constructed by Bis-(4-pyridyl)thiazolo[5,4-d]thiazole Containing Multi-electron Donor-acceptor Core

Constructed from 2,5-bis(4-pyridyl)thiazolo[5,4-d]thiazole(Py2TTz),sulfate anions and metal ions Cd(Ⅱ),a new 3D luminescent metal-organic framework(LMOF)with go...     

Liquid-crystalline behaviour of some bis(4-alkyloxyphenyl) thiazolo [5,4-d] dithiazoles

The preparation of liquid-crystalline 2,5-bis(4-alkyloxyphenyl) thiazolo [5,4-d] dithiazoles (ATT_n), in which the alkyl group is C_nH_{2n + 1} (where n = 1 to 10, 12), has been described. Mesomorphic properties and phase transitions as determined by polarizing hot stage microscopy and differential scanning calorimetry are discussed as a function of the number of carbon atoms in the alkyloxy chain. The exhibition of tilted smectic phases (smectic C and smectic I) by these compounds is an interesting feature since there is no significant central dipole moment transverse to these molecules.     

Synthesis and properties of thiazolo[5,4-d]pyrimidine 1-oxides

Synthesis and properties of hitherto unknown thiazolo[5,4-d]pyrimidine 1-oxides are described. For example, the reaction of 6-chloro-1,3-dimethyl-5-nitrouracil (I) with methyl thioglycolate in the presence of excess triethylamine afforded 2-methoxycarbonyl-4,6-dimethylthiazolo[5,4-d]pyrimidine-5,7-(4H,6H)dione 1-oxide (IIIa), which is a versatile intermediate for the preparation of various thiazolo[5,4-d]pyrimidine derivatives.     

High molecular weight broad band-gap polymers based on indolo[3,2-b]carbazole and thiazolo[5,4-d]thiazole derivatives for solar cells

Two broad band-gap high molecular weight polymers, poly[(5,11-di(9’-heptadecanyl)-indolo[3,2-b]carbazole-alt-2,5-bis(3-n-octylthiophene-2-yl)-thiazolo[5,4-d]thiazole (PICzOTzTz) and poly[(5,11-di(9’-heptadecanyl)-indolo[3,2-b]carbazole-alt-2,5-bis(3-n-n-dodecylthiophene-2-yl)-thiazolo[5,4-d]thiazole]) (PICzDOTzTz), consisting of indolo[3,2-b]carbazole (ICz) and thiazolo[5,4-d]thiazole (TzTz) derivatives were synthesized by Suzuki polycondensation. Their physical, electrochemical and optical properties were characterized in details. The thermogravimetric analysis displayed high thermal stability, and 5% degradation temperatures of PICzOTzTz and PICzDOTzTz were 427 and 435°C, respectively. The optical band gaps of PICzOTzTz and PICzDOTzTz were 2.13 and 2.07 eV, respectively. The hole mobilities of PICzOTzTz and PICzDOTzTz were investigated by the space charge limited current (SCLC) method, which gave the mobility values of 7.21 × 10^–5 and 1.57 × 10^–4 cm²/(V s) for each polymer, respectively. Through the photo-voltaic characterization in polymer solar cells, they showed that the power conversion efficiencies of PICzOTzTz and PICzDOTzTz were 0.64 and 0.99%, respectively.     

Synthesis of thiazolo[5,4-b]pyridine-2-carboxamides

A convenient procedure was developed for preparation of thiazolo[5,4-b]pyridine-2-carboxamides by oxidation of monothiooxamides synthesized from 3-aminopyridine.     

Synthesis of 2-phenylthieno[3,2-d]oxazole and 2-phenylthieno[3,2-d]thiazole

2-Phenylthieno[3,2-d]oxazole and 2-phenylthieno[3,2-d]thiazole were obtained by cyclization of the corresponding 2-phenyloxazole and 2-phenylthiazole derivatives. Their spectra and chemical properties were studied, and the pK_a values of carboxylic acids with other two-ring systems with a condensed thiophene ring were also compared.See [1] for our preceding communications.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 474–476, April, 1979.     

Facile and efficient synthesis of 5,7-disubstituted thiazolo[5,4-d] pyrimidine-4,6(5H,7H)-diones

A facile and efficient approach was developed to access 5,7-disubstitued thiazolo[5,4-d]pyrimidine-4,6(5H,7H)-diones through condensation of N-substituted 5-amino-4-carbethoxythiazole with structurally diverse isocyanates in the presence of sodium hydride.The easy availability of substrates and tolerance of structural diversity in this reaction make it attractive to be used for construction of libraries in drug discovery process.     

Synthesis of 2-methylphenanthro[2, 1-d]thiazole

2-Methylphenanthro[2, 1-d]thiazole has been synthesized by the oxidative cyclization of 2-thioacetylaminophenanthrene.     

聚丙烯酸[2,5-双(对甲氧基苯甲酰氧基)苄酯]及聚甲基丙烯酸[2,5-双(对甲氧基苯甲酰氧基)苄酯]的合成

周其凤等曾报道聚丙烯酸［２,５－双（对甲氧基苯甲酰氧基）节酯］［１］和聚甲基丙烯酸［２,５－双（对甲氧基苯甲酰氧基）苄酯］［２］的合成．但后来的研究发现,在合成单体的条件下出现的一种未见报道的异常反应［３］使产物成分复杂化,因此当时报道的聚合物可能不是聚丙烯酸［２,５－双－（对甲氧基苯甲酰氧基）苄酯］或聚甲基丙烯酸［２,５－双（对甲氧基苯甲酰氧基）苄酯］,而可能是共聚物．针对这一问题,我们重新设计了合成路线以避免发生上述副反应,成功地合成了丙烯酸或ａ－甲基丙烯酸［２,５－双－（对甲氧基苯甲酰氧基…     

A one-step synthesis towards new ligands based on aryl-functionalised thiazolo[5,4-d]thiazole chromophores

A general synthesis of disubstituted thiazolo[5,4-d]thiazoles was achieved by condensing two equivalents of an aryl aldehyde with dithiooxamide in nitrobenzene at 130 °C for 24 h. The method is tolerant to a range of aromatic aldehydes including derivatives of pyridine, quinoline, mono- and dihydroxybenzene. An X-ray crystal structure of 2,5-bis(2-hydroxy-3,5-di-tert-butylphenyl)thiazolo[5,4-d]thiazole was obtained confirming the proposed formulation, together with supporting spectroscopic data that suggests that for the 2-hydroxyphenyl derivatives intramolecular hydrogen bonding exists in both solution and solid states.     

Synthesis and characterization of a thiazolo[5,4-d]thiazole-based copolymer for high performance polymer solar cells

A highly processable, new semiconducting polymer, PCDTTz, based on alternating thiazolothiazole and carbazole units was synthesized. The new polymer exhibited a field-effect carrier mobility of up to 3.8 × 10(-3) cm(2) V(-1) s(-1) and bulk heterojunction solar cells made from PCDTTz produced a power conversion efficiency of 4.88% under AM 1.5 G (100 mW cm(-2)) conditions.     

Preparation of halogenated derivatives of thiazolo[5,4‐d]thiazole via direct electrophilic aromatic substitution

Chlorination and bromination reactions of thiazolo[5,4‐d]thiazole led to the generation of its mono‐ and dihalogenated derivatives. These are the first instances of successful direct electrophilic aromatic substitution in the thiazolo[5,4‐d]thiazole ring system. X‐ray analysis demonstrates that both 2‐bromothiazolo[5,4‐d]‐thiazole and 2,5‐dibromothiazolo[5,4‐d]thiazole are planar structures, with strongly manifested π‐stacking in the solid state. Theoretical analysis of the pyridine‐catalyzed halogenation (MP2/6‐31+G(d) and B3LYP/6‐31+G(d) calculations) reveals that introduction of one halogen actually leads to a slightly enhanced reactivity towards further halogenation. Several halogenation mechanisms have been investigated: 1) The direct C‐halogenation with N‐halopyridine as electrophile; 2) C‐halogenation via intermediate N‐halogenation, and 3) C‐halogenation following an addition ‐ elimination pathway, with intermediate formation of a cyclic halonium ion. The theoretical studies suggest that the direct C‐halogenation is the favored mechanism.