A selective, high-yielding procedure for the preparation of Bisphenol A cyclic oligomeric carbonates via a triethylamine-catalyzed hydrolysis/ condensation reaction of bis (chlorof ornate) is described. The reaction produces cyclic oligomers in 80-90% yield, along with about 15 % high molecular weight polymer, but with almost total exclusion of linear oligomers. The structure of the amine catalyst controls the selectivity of cyclic vs linear vs polymer formation. Use of other amine catalysts can lead to different products. Use of pyridine as catalyst, for example, affords linear oligomers in 99% yield, with very low yields of cyclics. Polymerization of the cyclic oligomers to polycarbonate with Mv = 50 000-300 000 is achieved by heating at 300 °C for 15 min in the presence of various basic catalysts. The preparation of authentic oligomeric linear and cyclic materials is also described.

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hydroxy-2,5,5-trimethyldecalin (Table I), NMR chemical shifts and coupling constants (Table II), a drawing illustrating the shielding of the axial methyl group in 5b (Figure 1), and the 360-MHz NMR spectrum of 2c with various amounts of shift reagent added (Figure 2) (4 pages). Ordering information is given on any current masthead page.

Studies have been carried out with the tosylate of the monomethyl ether of polyethylene glycol (MeO–PEG–OTs) and with low molecular weight models to assess whether the neighboring oxygen at position 3 or 6 provides the driving force for hydrolytic cleavage of these activated derivatives. Our results reveal that MeO–PEG–OTs undergoes hydrolysis by competitive pathways. Water directly displaces the tosylate group to give the original PEG alcohol and the oxygen at position 6 nucleophilically displaces the tosylate group to give a cyclic oxonium ion as an intermediate. This intermediate can react by three pathways. First, it can lead to the production of the original PEG alcohol by attack of water on a ring carbon; second, dioxane and a lower molecular weight PEG alcohol is produced by water attack at the nonring carbon next to the charged oxygen; and third dioxane can be displaced by the oxygen atom at position 6 in the chain.

The preparation and polymerization of a variety of cyclic oligomeric carbonates containing diverse functionality is described. The preparation of bisphenols containing ether, amide, ester, urethane, etherketone, or ethersulfone functionalities is described. The functionalized bisphenols were converted to dichloroformates via phosgenation, and were subjected to cyclization reactions, forming cyclic oligomeric carbonates containing various functionality. Anionic, ring‐opening polymerization of the cyclic oligomers leads to high molecular weight polymers containing carbonate and other functionality. Depending on the nature of the functionalized bisphenol starting material, the product polymers may be alternating, block, or random copolymers.