Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRIranian Journal of Chemistry and Chemical Engineering1021-998615219961201Methalloporphirins Catalyze Regio and Chemoselective Silylation of Hydroxy Groups with Hexamethyldisilazane (HMDS)54561043110.30492/ijcce.1996.10431ENHabib FirouzabadiDepartment of Chemistry, Faculty of Science, Shiraz University, Postcode 71454, Shiraz, I.R. IRANZohreh KhayatDepartment of Chemistry, Faculty of Science, Shiraz University, Postcode 71454, Shiraz, I.R. IRANAli Reza SardarianDepartment of Chemistry, Faculty of Science, Shiraz University, Postcode 71454, Shiraz, I.R. IRANShahram TangestaninejadDepartment of Chemistry, Faculty of Science, Shiraz University, Postcode 71454, Shiraz, I.R. IRANJournal Article19950624<em>Metalloporphirins; Cu(TPP), Mn(TPP)Cl, CO(TPP), Fe(TPP)Cl, zn(TPP) and Mn(OBP)Cl catalyze region and chemoselective silylation of hydroxyl groups with HMDS. Fe(TPP)Cl is the most effective catalyst and silylation occurs immediately in its presence at room temperature.</em>Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRIranian Journal of Chemistry and Chemical Engineering1021-998615219961201Polymer Supported Zinc Borohydride: A Stable, Efficient, Selective, and Regenerable Reducing Agent for Variety of Organic Compounds63711043310.30492/ijcce.1996.10433ENBahman TamamiDepartment of Chemistry, Faculty of Science, Shiraz University, Postcode 71454, Shiraz, I.R. IRANMoredin GoudarzianDepartment of Chemistry, Faculty of Science, Shiraz University, Postcode 71454, Shiraz, I.R. IRANJournal Article19951106<em>The difficult to handle and store zinc borohydride, Zn(BH<sub>4</sub>)<sub>2</sub>, is stabilized by supporting it on polyvinylpyridine. This new mild, efficient, selective, and regenerable polymer supported borohydride reducing agent reduces a variety organic compounds such as, aldehydes, </em><em>a</em><em>-</em><em>b</em><em>-unsaturated carbonyl compounds, acid chlorides, epoxides, disulfides, as well as reductive acetylation of carbonyl compounds. It absolutely discriminates aldehydes from ketones.</em> Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRIranian Journal of Chemistry and Chemical Engineering1021-998615219961201Synthesis of Some New Enaminoketones, Analogous of Milrinone, 4,Pyrones and Related 4-Pyridones76801043510.30492/ijcce.1996.10435ENAziz ShahrisaDepartment of Organic Chemistry, Faculty of Chemistry, Tabriz University, Postcode 51664, Tabriz,, I.R. IRANSalar HemmatiDepartment of Organic Chemistry, Faculty of Chemistry, Tabriz University, Postcode 51664, Tabriz,, I.R. IRANJournal Article19960116<em>Synthesis of 4-(N,N- dimethylamino)-3-aryl-3-butene-2-one, ethyl-5-aryl-4-oxo-4H-pyran-2-carboxylate, ethyl-5-aryl-4-pyridones-2-carboxylate and 5-aryl-3-cyano-5-methyl-2-pyridones (aryl=3-thienyl, 2-furyl) are described.</em>Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRIranian Journal of Chemistry and Chemical Engineering1021-998615219961201Probing the Cure and Postcure Reactions in Polyurethanes by FTIR and GPC87921043710.30492/ijcce.1996.10437ENHamed SalehiDepartment of Chemistry, Faculty of Science, Tarbiat Modarres University, P.O. Box 14155-4838 Tehran, I.R. IRANMozaffar EslamiResearch Institute of Petroleum Industry(RIPI), P.O. Box 18745-4391 Tehran, I.R. IRANMohammad Nabi SarboloukiInstitute of Biochemistry and Biophysics, Tehran University, P.O. Box 13145-1384 Tehran, I.R. IRANJournal Article19940628<em>Fourier transform infrared (FTIR) and gel permeation chromatography (GPC) wre respectively utilized in determining the changes in isocyanate (NCO) concentration and molecular weight (MW) and its distribution (MWD) in polyurethanes during their cure and postcure stages. Samples, originally cured at 45°C, were taken through accelerate aging tests at various temperatures. The FTIR and GPC analytical conditions were optimized, for both molecular weight and molecular weight distribution and NCO group determination. In FTIR spectroscopy Beer's law was obeyed over the ranges: 2.33-22.34 and 0.03-1.61 mmol lit<sup>-1</sup>. RSD, detection limit and molar absortivity were found to be 1.46%, 4</em><em>´</em><em>10<sup>-6 </sup>mol lit<sup>-1</sup> and 1095 lit mol<sup>-1</sup> cm<sup>-1 </sup>respectively. It was found the NCO concentration decreases with the progress of polymerization and at the same time MW of </em><em>the sol increases, going through a maximum and then decreases to a constant level. The time to reach this level and termination of NCO concentration, i.e., the end of polymerization decreases with the increase in temperature. The results obtained from GPC and FTIR methods in following the different steps of polymerization as well as those from the linear plots of the end time of reaction vs. the 1/T, were in good agreement.</em>