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In this work, we have synthesized a series of donor-acceptor type molecules involving electron donor diarylamines/heterocyclic amines and electron acceptor 9,10-anthraquinone by employing palladium catalyzed C−N bond forming amination reaction in good yield and fully characterized. Absorption spectra of all the synthesized molecules showed an intramolecular charge transfer (ICT) transitions in the range of 417−554 nm. Electrochemical properties of the compounds were studied by cyclic voltammetry (CV). The HOMO and LUMO energy levels of synthesized compounds were found in the range of −5.18 to −5.79 eV and −3.22 to −3.53 eV respectively as calculated by CV. Theoretical studies were also carried out by using DFT and TD-DFT calculation. On the basis of HOMO and LUMO energy levels, synthesized compounds could be used as ambipolar materials in organic electronics.

Imidazoanthraquinone derivatives with extended π conjugation were synthesized and characterized. Palladium-catalyzed Suzuki–Miyaura and Sonogashira couplings were employed to synthesize these derivatives. Photophysical and electrochemical studies of the new imidazoanthraquinone derivatives were performed, and their absorption and emission maxima were observed in a wide visible range. The photophysical studies revealed the formation of charge-transfer complexes. Cyclic voltammetry provided good estimates of the reduction and oxidation potentials of these compounds and eventually the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. Electrochemical studies revealed low-lying ELUMO values of ca. –3.7 eV for these compounds. The donor–acceptor architecture and HOMO–LUMO energies were further studied through DFT calculations. On the basis of the ELUMO values of these compounds, photoquenching experiments were performed in the presence of the electron donor poly(3-hexylthiophene) (P3HT). These experiments suggest that these compounds could be used as electron acceptors in heterojunction solar cells.

A rapid assembly of the tetracyclic core of marine diterpenoids related to puupehenone and kampanols by DielsAlder reaction of 2-ethenyl-1,3,3-trimethylcyclohexene with 4H-chromen-4-one (¼ 4H-1-benzopyran-4-one) dienophiles is described. Introduction. -T heDielsAlder reactions of 2-ethenyl-1,3,3-trimethylcyclohexene with dienophiles like dimethyl acetylenedicarboxylate (1), unsymmetrical 1,4-benzo- quinones (2), 1,4-benzoquinone (3), substituted 1,4-benzoquinones (4), 2-(methoxy- carbonyl)-4,4-dimethylcyclohex-2-enone (5), 3-((E)-(methoxycarbonyl)prop-2-eno- yl)-1,3-oxazolidin-2-one (6), acetylenedicarbaldehyde (7), (S)-5-(tert-Butyl)-3-hy- droxy-2-isopropyl-1,4-benzoquinone (8), and conjugated ketones (9) have been reported. There are very few reports on (4 þ 2) cycloaddition reactions using 4H- chromen-4-ones (¼ 4H-1-benzopyran-4-ones) as dienophiles, and in all these cases an activating functionality likeCHO, � COR, � COOR, � CN, � Ar, etc. at C(3) have been utilized (10). Only one DielsAlder reaction of 2-ethenyl-1,3,3-trimethylcyclohexene with 6-bromo-3-cyano-4H-chromen-4-one has been reported (10a).

A mild, efficient method utilizing a copper-diamine catalyst at room temperature is reported for the coupling of hindered imidazoles with unsubstituted, ortho-substituted, and bis-ortho-substituted boronic acids in good to excellent yields. Aryl halides do not reaction under these conditions permitting sequential N-arylation reactions.

The main objective of this study was to assess the severity of iodine deficiency disorders (IDD) in the adult populations of the Baroda and Dang districts from Gujarat, western India using biochemical prevalence indicators of IDD. The other aim of this study was to establish a biochemical baseline for adequate iodine intake as a result of program evolution in the face of multiple confounding factors, like malnutrition and goitrogens responsible for goiter. A total of 959 adults (16-85 years) were studied from two districts (Baroda and Dang) and data was collected on dietary habits, anthropometric and biochemical parameters such as height, weight, urinary iodine (UI) and blood thyroid stimulating hormone (TSH). Drinking water and cooking salt were analyzed for iodine content. All subjects, irrespective of sex and district, showed median UI = 73 microg/L and mean blood TSH +/- SD = 1.59+/-2.4 mU/L. Seven per cent of the studied population had blood TSH values > 5 mU/L. Females in Baroda and males from Dang district were more affected by iodine deficiency as shown by a lower median UI. Mean TSH was significantly higher in women from both districts as compared to men (P = 0.001). The blood spots TSH values > 5 mU/L were seen in 20% of women from Dang. The normative accepted WHO values for UI and TSH for the severity of IDD as a significant health problem are not available for target population of adults. Urinary iodine normative limits and cut-offs are established for school-aged children. Blood spot TSH upper limit and cut-off values are available for neonate populations. The IDD has not been eliminated so far, as more than 20% of both male and female subjects had UI < 50 microg/L. Males were more malnourished than females in both districts (P < 0.05). Pearl millet from Baroda contained flavonoids like apigenin, vitexin and glycosyl-vitexin. Dang district water lacked in iodine content. Iodine deficiency disorder is a public health problem in Gujarat, with the Baroda district a new pocket of IDD. High amounts of dietary flavonoids in Baroda and Dang, malnutrition and an additional lack of iodine in Dang water account for IDD.

The Kerr effect in an intensity modulated direct detection subcarrier multiplexed system with multiple optical carriers is investigated in this paper. An expression for inteference power spectrum is derived taking into consideration the laser phase noise and Kerr effect. The derivation is carried out first for the case of two optical carriers, and then generalised for the lightwave system with N optical carriers.

A rapid assembly of the tetracyclic core of marine diterpenoids related to puupehenone and kampanols featuring a Lewis acid catalyzed [4+2] cycloaddition reaction of 1,3,3-trimethyl-2-vinyl-1-cyclohexene and chromone dienophiles is described.

N-Aryl-β-amino acetates, obtained by opening epoxides with aromatic amines followed by acetylation of the hydroxyl group, were resolved using crude pig liver esterase (PLE) enzyme in DMSO in high enantiomeric excess.

A variety of ketones undergo an allylation reaction with tetra-allyltin in the presence of a catalytic amount of Cu(OTf)2 or Sn(OTf)2. The method was found to be superior to most of the known methods, which are efficient only with aldehydes.

A mild, efficient method utilizing a copper-diamine catalyst at room temperature is reported for the coupling of hindered imidazoles with unsubstituted, ortho-substituted, and bis-ortho-substituted boronic acids in good to excellent yields. Aryl halides do not reaction under these conditions permitting sequential N-arylation reactions.

[Co(P1)], which was designed on the basis of potential hydrogen-bonding interactions in the metal-nitrene intermediate, is a highly active aziridination catalyst with azides. [Co(P1)] can effectively aziridinate various aromatic olefins with arylsulfonyl azides under mild conditions, forming sulfonylated aziridines in excellent yields. The Co-based system enjoys several attributes associated with the relatively low cost of cobalt and the wide accessibility of arylsulfonyl azides. Furthermore, it generates stable dinitrogen as the only byproduct.

Asymmetric version of allylic oxidation of oletins to a1lylic esters is an important transformation, The reaction is performed usually using peresters in the presence of a metal catalyst in a chiral environment. Copper catalyst was mainly used by most of the people. Development in this area has been summarized here in a chronological manner. Initially, a modest asymmetric induction in this reaction was achieved by using a variety of chiraI amino acids. Lately, a variety of chiral ligands have been introduced to obtain high enantiomeric excess (up to 93% ee) in the allylic oxidation of a variety of cyclic oletins. One of the drawbacks of the reaction was longer time ranging from a week to a month for completion. This shortcoming was overcome to some extent by using phenylhydrazineJphenylhydrazone in the reaction mixture. The reason for enhancement in rate of the reaction is not yet clear, but the reaction can now be completed within a day or two without loosing enantioselectivity. Despite so much progress in this area, the reaction is restricted only to cyclic oletins. Acyclic oletins do not give high asymmetric induction.

Enantioselective addition of phenylacetylene to various aldehydes was studied in the presence of inexpensive and commercially available Cinchona alkaloids. A maximum of 85% ee was obtained using cinchonidine in the presence of Ti(O i Pr) 4 .

Aromatic electrophilic substitution reactions such as alkylation, acylation, benzoylation, and sulfonylation were studied in the presence of a catalytic amount of Cu(OTf) 2 and Sn(OTf) 2 . Cu(OTf) 2 was very efficient for alkylation, acylation, and benzoylation reactions. However, in case of sulfonylation reactions, Sn(OTf) 2 gave better results.

Cinetique de la synthese du methanol dans un reacteur differentiel a des pressions allant de 3 a 15 atm et des temperatures de 250 a 290°C