The application of silica-supported TEMPO as a recyclable catalyst in the Anelli oxidation of alcohols is reported. The catalyst is easily obtained in a one-step reductive amination procedure starting from a commercially available aminopropyl-functionalized silica. Details of the synthesis of the supported catalyst and its analysis by MAS NMR are presented. Various alcohol oxidations according to the Anelli protocol have been carried out and the stability of the applied silica-supported TEMPO has been studied.

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Poly(esters amide)s from adipic anhydride and α,ω‐amino alcohols were obtained by polycondensation of α‐carboxyl‐ω‐hydroxyl amides under mild conditions in solution or by bulk polycondensation at elevated temperatures. For the polycondensation in bulk the influence of catalyst and of temperature on the number‐average molecular weight was studied. At a temperature of 170 °C the polycondensation process is followed by a ring‐closing depolymerisation and the formation of cyclic ester amides. Ten‐ to fourteen‐membered cyclic ester amides were obtained and characterized. The ring‐opening polymerisation of these cyclic ester amides leads, in a controlled mode, to poly(ester amide)s. The interconversion of poly(ester amide)s and cyclic ester amides by ring‐closing depolymerisation and ring‐opening polymerisation is possible. The poly(ester amide)s from adipic anhydride and homologous α,ω‐amino alcohols H2N(CH2)xOH (x = 2–6) are semicrystalline materials, their melting points show the odd/even effect observed for [n]‐polyamides and [n]‐polyurethanes.

Alternating poly(ester amide)s 6a–e from succinic anhydride and α,ω‐amino alcohols H2N—(CH2)x—OH (x = 2–6) 2a–e were obtained in two steps: α‐carboxyl‐ω‐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 α,ω‐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

The ring-opening polymerization of the cyclic ester amide (cEA, 2) (systematic name, 1-oxa-7-aza-cyclotridecane-8,13-dione)sprepared from adipic anhydride and 1-amino-5-pentanolsin the melt at temperatures above 145 °C with Bu2Sn(OMe)2, Ti(OBu)4, Al(O-sec-Bu)3, or Sn(octoate)2 as initiator yields the poly(ester amide) (PEA, 3) (systematic name, poly(5-(5-oxypentylcarbamoyl)pentanoate) with regular microstructure. This poly(ester amide) is a semicrystalline material with a melting point of 108 °C. The elementary chain growth reaction proceeds by a coordination insertion mechanism in analogy to the polymerization of lactones. The monomer-to-initiator ratio and the conversion determine the numberaverage molecular weight. By using hydroxy telechelic poly(ethylene oxide) with Sn(octoate) 2 as initiator poly(ester amide)-block-poly(ethylene oxide) and poly(ester amide)-block-poly(ethylene oxide)-block-poly-(ester amide) were obtained. Kinetic studies for different monomer-to-initiator ratios, different temperatures and initiators reveal that the ring-opening polymerization is a first-order reaction with respect to the monomer and shows no termination and transfer reactions.

Alternating poly(ester amide)s 6a -e were prepared by polycondensation of α-carboxyl-ω-hydroxyamides 3a -e which were obtained by aminolysis of glutaric anhydride (1) and α,ω-aminoalcohols, H 2 N-(CH 2 ) x -OH (x = 2 -6) 2a -e. The polycondensation was performed in dimethylformamide solution using a carbodiimide as activating agent, or in bulk with Bu 2 Sn(OMe) 2 , Ti(OBu) 4 and Sn(octoate) 2 as a catalyst. For the polycondensation in bulk, the influence of catalyst and of temperature on the number-average molecular weight was studied. 1 H NMR analyses of the poly(ester amide)s clearly show the alternating microstructure. The poly(ester amide)s from glutaric anhydride and the homologous series of α,ω-aminoalcohols are semicrystalline materials; their melting points show the odd/even effect observed for other poly(ester amide)s.