Bicyclic oxalactam polymerization

In connection with studies on the ring-opening polymerization of cyclic acetals, we have undertaken investigations on the polymerization of bicyclic acetals, bicyclic oxalactone, and bicyclic oxalactam, which yield polysaccharide analogs, macrocyclic oligoesters, and a hydrophilic polyamide, respectively, some of which can be expected to be useful as novel speciality polymers. The monomers employed in the studies were prepared via synthetic routes presented in Scheme 1, starting from 3,4-dihydro-2H-pyran-2-carbaldehyde (acrolein dimer) I. 

A new class of hydrophilic polyamides, poly(tetrahydropyran-2,6-diylimino-carbonyl) 1 was prepared by the anionic polymerization of a bicyclic oxalactam (abbreviated as BOL, 2) 38-42). The resulting polyamide / has glass transition, fusion, and decomposition points at 130,260-285, and 315 °C, respectively, and its membrane can be obtained by casting from a polyBOL solution. The solubility parameter... 

Anionic polymerization of a sodium salt (61) of a bromosubstituted bicyclic lactam (60) is very unusual. It proceeds in dimethylformamide at 0 and 25 °C with elimination of sodium bromide and gives oligomers 62 having a bicyclic oxalactam ring in each repeating unit. [70]... 

The ring-opening polymerization of bicyclic oxalactams gives macromonomers (545,546). 

For 2-piperidone, quaternary salts and alkaline salts were investigated as polymerization initiators, and the rate of polymerization was related to the dissociation constant. A novel polyamide, poly(tetrahydropyran-2,6-diyalaminocarbonyl) has been reported and was prepared in THF or DMSO at or below room temperature by ring-opening of the bicyclic oxalactam 8-oxa-6-azabicyclo[3.2.]]octam-7-one. No activator system was required. 

Bicyclic oxalactam macromonomers can be synthesized by ring-opening polymerization as shown in equation... 

Sumitomo, H. and Okada, M. Ring-Opering Polymerization of Bicyclic Acetals, Oxalactone, and Oxalactam. Vol. 28, pp. 47—82. 

Ring-Opening Polymerization of Bicyclic Acetals, Oxalactone, and Oxalactam... 

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