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The coupling of 7-aryl-3,4-dihydro-4-oxothieno[3,2-d]pyrimidine-2-carboxylic acid with a primary alkylamineloaded acid-sensitive methoxy benzaldehyde (AMEBA) resin, a benzotriazol-1-yloxytris(dimethylamino) phosphonium hexafluorophosphate (BOP)-mediated amination reaction, and cleavage from the solid support yielded N-alkyl-4-(alkylamino)-7-arylthieno[3,2-d]pyrimidine-2-carboxamide derivatives. The progress of the reactions on solid phase was monitored through attenuated total reflectance-FTIR spectroscopy and was compared with representative solution-phase surrogates. Additionally, N-acylation (acid chloride, InF 3 , CH 3 CN, room temperature) and cyclization (DBN, 1,4-dioxane, 80 C) of a 3-amino-4-(4-t-butoxycarbonylphenyl) thiophene-2-carboxamide intermediate under previously unreported conditions provided 2-substituted thieno[3,2-d]pyrimidin-4(3H)-one derivatives, which were subsequently converted to 2-substituted 4-alkylamino-7-[4-(alkylaminocarbonyl)phenyl]thieno[3,2-d]pyrimidine derivatives through a reaction sequence consisting of a BOP-mediated amination reaction, t-butyl deprotection, and amide formation.

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The method to attach seed to crucible lid as well as seed quality is very important for obtaining high quality crystals. Therefore, modified seeding method was developed for improving adhesive layer between seed and graphite crucible lid. SiC single crystal grown with modified seeding method definitely exhibited lower micropipe density (MPD) and lower full width at half maximum (FWHM) values comparing with values from conventional seeding method. Etch pit density of SiC crystal was successfully decreased with using the modified seeding method.