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High-molecular-weight poly(1,4-butylene carbonate) (PBC) (M n : 40,000290,000) was prepared through the condensation polymerization of dimethyl carbonate (DMC) and 1,4butanediol (BD) in the presence of 0.05 mol % sodium alkoxide catalyst. The subsequent feeding of 15 mol % HOAOH, such as 1,6-hexanediol, 1,5-pentanediol, 1,4-cyclohexanedimethanol, or 1,4-benzenedimethanol and stirring at 190-150 C converted the extremely thick high-molecular-weight polymer to lowmolecular-weight macrodiols with GPC-measured M n $2000. The analysis of the 1 H NMR spectra indicated that the -A-units and 1,4-butylene units were randomly distributed in the resulting oligomers. The chopping of the high-molecular-weight PBC using either triols or tetraols such as glycerol propoxylate, 1,1,1-tris(hydroxymethyl)ethane, or pentaerythritol also afforded macropolyols containing branched chains with GPCmeasured M n $2000. When the chopped polymers were genuine PBCs, the resulting macrodiols or polyols were in a waxy state at room temperature. However, permanently oily compounds were obtained when the chopped polymers were prepared using 0.90 mole fraction of BD admixed with various other diols. The macrodiols and polyols synthesized in this study may have potential applications in the polyurethane industry.

Post-metallocenes were constructed for olefin polymerization using 1,2,3,4,7,8,9,10-octahydro[1,10]phenanthroline and 1,2,3,4-tetrahydro[1,10]phenanthroline derivatives. A series of zirconium complexes - LZrCl2(NHMe2)2 [L = 2,9-H2-C12H12N2 (4), 2,9-Me2-C12H12N2 (5), 2,9-nBu2-C12H12N2 (6), and 2,9-iPr2-C12H12N2 (7)] - and hafnium complexes - LHfCl2(NHMe2)2 [L = 2,9-H2-C12H12N2 (8), 2,9-Me2-C12H12N2 (9), 2,9-nBu2-C12H12N2 (10), and 2,9-iPr2-C12H12N2 (11)] - were synthesized via the reaction of octahydro[1,10]phenanthrolines (2,9-R2-C12H12(NH)2) with (Me2N)2MCl2 (DME). The reaction of 2,9-R2-C12H12(NH)2 with (PhCH2)2ZrCl2 in the presence of a small amount of THF afforded a series of THF adduct analogs, i.e., LZrCl2(THF)2 [L = 2,9-H2-C12H12N2 (12), 2,9-Me2-C12H12N2 (13), 2,9-nBu2-C12H12N2 (14), and 2,9-iPr2-C12H12N2 (15)]. The treatment of 12 and 13 with excess Me3Al resulted in the formation of unexpected complexes, i.e., (η(4)-LAlMe2)ZrCl2(Me) [L = 2,9-H2-C12H12N2 (16) and 2,9-Me2-C12H12N2 (17)], in which the Me2Al unit forms a five-membered ring through binding with the two nitrogen donors and the MeCl2Zr unit slips to an η(4)-binding mode containing the N-C-C-N fragment. The treatment of tetrahydro[1,10]phenanthrolines [2,9-R2-C12NH9(NH)] with M(CH2Ph)4 afforded tribenzyl zirconium complexes LZr(CH2Ph)3 - [L = 2,9-Me2-C12NH9N (18) and 2,9-nBu2-C12NH9N (19)] - and hafnium complexes - LHf(CH2Ph)3 [L = 2,9-Me2-C12NH9N (20), 2,9-nBu2-C12NH9N (21), and 2,9-iPr2-C12NH9N (22)]. The structures of 4, 5, 12, 17, and 22 were elucidated by X-ray crystallography. The newly prepared complexes were screened for ethylene/1-octene copolymerization activity: 12 and 16 were potent catalysts (activities of 74 × 10(6) g mol-Zr h(-1) at ∼120 °C under 30 bar ethylene) for the production of wax-like low-molecular weight polyethylene (Mn: ∼5000), which is widely used in industry.

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