A novel telechelic polystyrene having moderately strained cyclic ammonium, i.e., six-membered bicyclic quinuclidinium salt groups, has been synthesized, and mono-, di-, and tetracarboxylate counteranions were introduced by the ion-exchange reaction. A monocarboxylate, i.e., benzoate, counteranion was found to cause a selective ring-opening reaction of the quinuclidinium salt end group by the heat treatment at 110 °C. A single-cyclic polystyrene 2 was then produced in a high yield from the polymer precursor carrying a dicarboxylate, i.e., terephthalate, counteranion by the heat treatment in a diluted (0.1 g/L) toluene solution. Furthermore, a double-cyclic (8-shaped) polystyrene 3 was produced relevantly from another precursor carrying a tetracarboxylate, i.e., tetrakis((4-carboxylatophenyl)oxymethyl)methane, counteranion.

Both 2:1 and 1:1 couplings of alkylacetylenes with secondary amines were achieved using 8-quinolinolato rhodium catalysts and CsF. The 2:1/1:1 selectivity was switched by choosing the reaction solvent. In DMA, an unprecedented 2:1 coupling reaction of alkylacetylenes with amines proceeded to give 2-aminodiene products. One-pot 2:1 coupling/reduction provided rapid access to various allylamines, while one-pot coupling/hydrolysis gave enones as products. In toluene, anti-Markovnikov hydroamination occurred under relatively mild conditions to give 1:1 coupling products.

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Polystyrenes with various end groups were analyzed by time-of-flight secondary ion mass spectrometry (TOF-SIMS). These end groups were obtained by termination of the active anionic group by sulfonate or chlorosilane derivatives. Characteristic end group fragments for each sulfonate derivative were observed. On the one hand, for PS capped by methyl sulfonate, or -(CH(2))(4)-O-SO(2)-CH(3), almost complete end group fragment is observed at m/z 95 and a [O-SO(2)-CH(3)](-) molecular structure. On the other hand, when PS is terminated by silyl methyl sulfonate, or -Si(CH(3))(2)-(CH(2))(3)-O-SO(2)-CH(3), the most characteristic fragment in the fingerprint secondary ion mass spectrum is located at m/z 153 with [Si(CH(3))(2)-O-SO(2)-CH(3)](+) and the complete end group peak, [Si(CH(3))(2)-(CH(2))(3)-O-SO(2)-CH(3)](+), at m/z 201, is absent. According to the molecular structure, characteristic end group secondary ions can be emitted as complete or rearranged fragments. Various silylalkyl alcohol or sulfonate functionalities are analyzed and fragmentation pathways are discussed. To our knowledge, this is the first time that such rearrangement at silyl functions has been observed and demonstrated in fingerprint secondary ion mass spectra. Copyright 1999 John Wiley & Sons, Ltd.