Synthesis and characterization of new bi-functional monomers based on germarylene or silarylene units: 4,4′-(R1R2-silylene)bis(phenyl chloroformates) and 4,4′-(R1R2-germylene)bis(phenyl chloroformates)

Abstract

Abstract-Following the reaction route between a diphenol and phosgene/toluene solution in basic medium, six new bis(chloroformates) containing germarylene or silarylene units were synthesized with good yield. The variation on the structure is due to the nature of the groups bonded to the heteroatom. Therefore, combinations of Me, Et and Ph groups were used. 4,4 -(Diethylsilylene)bis(phenyl chloroformate), 4,4 -(ethylmethylsilylene)bis(phenyl chloroformate) and 4,4 -(diethylgermylene)bis(phenyl chloroformate) were obtained as a slightly yellow oil, while 4,4 -(diphenylsilylene)bis(phenyl chloroformate), 4,4 -(methylphenylsilylene)bis(phenyl chloroformate) and 4,4 -(diphenylgermylene)bis(phenyl chloroformate) were obtained as a white solid. The new bi-functional monomers were characterized by FT-IR, 29 Si-, 13 C-and 1 H-NMR spectroscopy and elemental analysis. The T m of the products in general was higher in samples containing germanium as the central atom, compared to those containing silicon.

New cardo silylated poly(azomethine)s containing 9,9′‐diphenylfluorene units as materials with Brønsted acid‐dependent fluorescence

“…These last two signals were also evidenced in the spectrum of PAzMC2. Both samples showed a signal in the Si NMR spectrum, whose chemical shift was in accordance with the magnetic environment of the silicon atom . For PAzMC1 which contains a PhSi(CH 3 ) 2 Ph moiety, the signal was evidenced at ca −8 ppm (Fig.…”

“…Both spectra showed weak bands of aldehyde ( ca 1700 and 2880 cm −1 ) which were associated with a terminal monomer unit. As for other silylated PAzMs prepared by our research group using the same dialdehyde monomers, bands associated with amino‐terminal groups were not evidenced …”

“…Both samples showed a signal in the 29 Si NMR spectrum, whose chemical shift was in accordance with the magnetic environment of the silicon atom. 32 For PAzMC1 which contains a -PhSi(CH 3 ) 2 Phmoiety, the signal was evidenced at ca −8 ppm ( Fig. 3(b)) while for PAzMC2, the signal appeared at ca −13 ppm in agreement with the -PhSi(Ph) 2 Ph-segment.…”

Biochemical and Molecular Analysis of Laccase Enzyme in Saprobic Fungus; Sordaria fimicola

“…**************** LACN6 NPGAWLMHCHIAWHVSGGLSNQFLERAQDLKNGISNADKQAFNNNCNAWRAYFPDNAPFP 600 LACN7 NPGAWLMHCHIAWHVSGGLSNQFLERAQDLKNGISNADKQAFNNNCNAWRAYFPDNAPFP 600 LACSF13 NPGAWLMHCHIAWHVSGGLSNQFLERAQDLKNGISNADKQAFNNNCNAWRAYFPDNAPFP 600 LACS2 NPGAWLMHCHIAWHVSGGLSNQFLERAQDLKNGISNADKQAFNNNCNAWRAYFPDNAPFP 600 LCAS1 NPGAWLMHCHIAWHVSGGLSNQFLERAQDLKNGISNADKQAFNNNCNAWRAYFPDNAPFP 600 RefE NPGSWLMHCHIAWHVSGGLSNQFLERAQDLRNSISPADKKAFNDNCDAWRAYFPDNAPFP 600 ***:**************************:*. ** ***:***:**:************* LACN6 KDDSGLRSGVKAREVKMEW-619 LACN7 KDDSGLRSGVKAREVKMEW-619 LACSF13 KDDSGLRSGVKAREVKMEW-619 LACS2 KDDSGLRSGVKAREVKMEW-619 LCAS1 KDDSGLRSGVKAREVKMEW-619 RefE KDDSGLRSGVKAREVKMKW-619 *****************:* report of Terraza et al (2007), according to which (pI) of fungal laccase was in range of 4-5.…”

Novel aromatic polyimides derived from 2,8-di(3-aminophenyl)dibenzofuran. Synthesis, characterization and evaluation of properties

“…1 H and29 Si NMR spectra of PI-SiDA. This chemical shift is expected when the silicon atom is surrounded by two aromatic rings and two methyl groups27,28 . The signal at high field corresponds to the hydrogens H2 of the dianhydride moiety.…”