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Hydroxy Amides (hydroxy + amide)
Selected AbstractsChemInform Abstract: Highly Enantioselective Addition of Methyl Propiolate to Aldehydes Catalyzed by a Titanium(IV) Complex of a ,-Hydroxy Amide.CHEMINFORM, Issue 24 2010Tao Xu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Highly Diastereoselective Synthesis of ,-Hydroxy Amides from ,-Keto Amides.CHEMINFORM, Issue 19 2005Giuseppe Bartoli Abstract For Abstract see ChemInform Abstract in Full Text. [source] Aromatic polybenzoxazoles containing ether,sulfone linkagesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2001Sheng-Huei Hsiao Abstract A series of poly(o -hydroxy amide)s having both ether and sulfone linkages in the main chain were synthesized via the low-temperature solution polycondensation of 4,4,-[sulfonylbis(1,4-phenylene)dioxy]dibenzoyl chloride and 4,4,-[sulfonylbis(2,6-dimethyl-1,4-phenylene)dioxy]dibenzoyl chloride with three bis(o -aminophenol)s including 4,4,-diamino-3,3,-dihydroxybiphenyl, 3,3,-diamino-4,4,-dihydroxybiphenyl, and 2,2-bis(3-diamino-4-hydroxyphenyl)hexafluoropropane. Subsequent thermal cyclodehydration of the poly(o -hydroxy amide)s afforded polyethersulfone benzoxazoles. Most of the poly(o -hydroxy amide)s were soluble in polar organic solvents such as N -methyl-2-pyrrolidone; however, the polybenzoxazoles without the hexafluoroisopropylidene group were organic-insoluble. The polybenzoxazoles exhibited glass-transition temperatures (Tg) in the range of 219,282 °C by DSC and softening temperatures (Ts) of 242,320 °C by thermomechanical analysis. Thermogravimetric analyses indicated that most polybenzoxazoles were stable up to 450 °C in air or nitrogen. The 10% weight loss temperatures were recorded in the ranges of 474,593 °C in air and 478,643 °C in nitrogen. The methyl-substituted polybenzoxazoles had higher Tg's but lower Ts's and initial decomposition temperatures compared with the corresponding unsubstituted polybenzoxazoles. For a comparative purpose, the synthesis and characterization of a series of sulfonyl polybenzoxazoles without the ether group that derived from 4,4,-sulfonyldibenzoyl chloride and bis(o -aminophenol)s were also reported. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2262,2270, 2001 [source] Ketopinic Acid Derived Bis(hydroxy amides) as Cheap, Chiral Ligands for the Enantioselective Ethylation of Aromatic AldehydesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 9 2010Tomás de las Casas Engel Abstract Readily accessible, C2 - and pseudo- C2 -symmetric bis(hydroxy amides), derived from commercially available (+)-ketopinic acid and protic diamines, are promising, cheap, chiral ligands for the synthetically valuable, enantioselective addition of organozinc reagents to carbon electrophiles. A series of ligands of this type, having key structural differences, has been synthesized and tested in the enantioselective ethylation of benzaldehydes and (E)-cinnamaldehyde, in order to gain information on the origin of ligand efficiency. The results obtained allow for the definition of a privileged structural pattern for the design of improved cheap ligands and support interesting models proposed for both the acting catalytic species and the controlling transition states. The most efficient ligands proved to be less efficient than commercially available (,)-MIB; nevertheless, an impressive efficiency level was obtained, which should sustain interest in this cheap type of ligands. [source] o -Amine-Assisted Cannizzaro Reaction of Glyoxal with New 2,6-DiaminoanilinesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2009Yuhki Irie Abstract The preparation of several new o -amine-substituted anilines was achieved according to a new bifunctional molecular design, and their reactions with glyoxal were conducted. Cannizzaro reactions of glyoxal proceeded using specifically designed anilines, such as 2,6-dipyrrolidinyl-, 2,6-dipiperidinyl-, 2,6-dimorpholinyl-, and 2-pyrrolidinyl-aniline, which are new and can easily be synthesized by substitution of halogen-substituted nitrobenzene with amines and subsequent reduction with hydrogen, to form ,-hydroxy acetamide and ,-amino acetamide derivatives, as a result of the Cannizzaro reaction. In comparison with the reaction of glyoxal with p -pyrrolidinylaniline to form a common diimine product, the reaction with o -pyrrolidinylaniline leads only to ,-hydroxy amides, strongly suggesting that the abnormal Cannizzaro reactions are attributed to the existence of basic nitrogen atoms at the o -positions, which suppress diimine formation and assist the generation of acetamides.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Alternating poly(ester amide)s from succinic anhydride and ,,,-amino alcohols: synthesis and thermal characterization,,POLYMER INTERNATIONAL, Issue 10 2003Thomas Fey Abstract Alternating poly(ester amide)s 6a,e from succinic anhydride and ,,,-amino alcohols H2N,(CH2)x,OH (x = 2,6) 2a,e were obtained in two steps: ,-carboxyl-,-hydroxy amides 3a,e were prepared from the starting materials in a highly selective reaction, followed by a polycondensation reaction. 1H and 13C NMR analyses of the poly(ester amide)s clearly reveal the alternating microstructure. The poly(ester amide)s with homologous ,,,-amino alcohols H2N,(CH2)x,OH (x = 2,6) are semi-crystalline materials, their melting points show the odd/even effect observed for [n]-polyamides and [n]-polyurethanes. Heating the poly(ester amide)s 6a,e yields the corresponding N -(hydroxyalkyl) imides 4a,e with no trace of cyclic ester amides. Theoretical calculations revealed that the cyclic ester amides 5a,e are clearly richer in energy than the isomeric N -(hydroxyalkyl) imides. These results show that cyclic ester amides can not be prepared from N -(hydroxyalkyl) imides by ring-enlargement reactions. Copyright © 2003 Society of Chemical Industry [source] ChemInform Abstract: Utilization of the Suzuki Coupling to Enhance the Antituberculosis Activity of Aryloxazoles.CHEMINFORM, Issue 34 2010Garrett C. Moraski Abstract A three-step process enables access to aryl oxazoles via formation of ,-hydroxy amides (III), cyclization to oxazolines (IV), and dehydration to provide oxazoles (V). [source] | |||||||||||||