Everything just clicks into place: Alkyne‐group functionalized polymer films that are deposited from the gas phase allow spatially defined immobilization of biomolecules, such as biotin, through the 1,3‐dipolar cycloaddition click reaction with azide derivatives (see scheme). Such biofunctional surfaces have applications in diagnostics and biosensors.

A selection of pseudo-geminally substituted [2.2]paracyclophanes, the alkynes 6, 7, 10, 11 a, and 11 b and the alkenes 8 and 9 were prepared for the study of intraannular reactions between functional groups in direct juxtaposition. Whereas 9 and 10 provide the corresponding cyclobutane and cyclobutene derivatives on irradiation (12 and 13, respectively), the bis-alkynes 7 and 11 b do not lead to a cyclobutadiene intermediate. In the latter case the "half-closed" butadiene derivative 17 was isolated. A Paterno-Büchi reaction took place on irradiation of 8 and 6, although the oxetene intermediate 21 produced in the second example did not survive the reaction conditions (ring-opening to 22). Bromine addition to 9, 10, and 7 occurred with high stereoselectivity (formation of the dibromides 27, 30, and 33, respectively), and is rationalized by postulating the formation of the cationic intermediates 26, 29, and 32, respectively. To study the interaction of a carbocation with a facing triple bond, the alcohol 34 was prepared from 6. On acid treatment ring closure to the triply-bridged phane 38 took place, accompanied by the hydration of the triple bond to the ketoalcohol 37. In an interesting intraannular [2+3]cycloaddition reaction the bis-acetylene 11 a, on treatment with n-butyl lithium, provided the cyclopentadiene derivative 42. That the two triple bonds of a pseudo-geminal diacetylene can engage in a cyclization reaction leading to the cyclopentadienone complex 44 was also shown by treating 11 b with iron pentacarbonyl.

The synthesis of seven ethynyl[2.2]paracyclophanes is described. The five diethynyl derivatives 4,5-diethynyl[2.2]paracyclophane (12), pseudo-gem-(13), pseudo-ortho-(14), pseudo-meta-(15), and pseudo-para-diethynyl[2.2]paracyclophane (16), the tetraethynyl compound 4,7,13,16-tetraethynyl[2.2]paracyclophane (17), and for comparison the mono-ethynylated hydrocarbon 4-ethynyl[2.2]paracyclophane (11) have been prepared. The structures of these new building blocks for carbon rich systems were determined by the usual analytical and spectroscopic methods.

This paper describes partially fluorinated poly-p-xylylenes prepared by CVD polymerization. The synthesis, characterization, and surface modification of two partially fluorinated polymer coatings, namely poly(4,12-dibromo-1,1,9,9-tetrafluoro-pxylylene) (2) and poly(4-heptadecafluorononanoyl-p-xylylene-co-p-xylylene) (4), is described. Polymer 2 is synthesized from 4,12-dibromo-1,1,9,9-tetrafluoro[2.2]paracyclophane (1), which is fluorinated at the aliphatic bridge, while 4-heptadecafluorononanoyl[2.2]paracyclophane (3), which contains a perfluorinated keto group at the aromatic ring, is used to synthesize polymer 4. Furthermore, the keto-functionalized polymer 4 introduces both extreme hydrophobicity and surface reactivity towards hydrazide-containing ligands.

Enhanced global delocalization throughout the “stepped” π‐electron systems of the [2.2]paracyclophane/dehydrobenzoannulene (PC/DBA) hybrids 1 and 2 is strongly suggested by a comparison of their electronic absorption spectra with those of model compounds with complete and interrupted classical aromatic delocalization. A distinct bathochromic shift (for 1) and greater absorption intensity at higher wavelengths (for 1 and 2) is observed versus the corresponding model hydrocarbons.