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A series of asymmetric and symmetric diols were prepared in high yields from biomass-derived feedstocks 5-hydroxymethyl furfural (HMF) and 2,5-diformyl furan (DFF) as potential replacements for bisphenol A (BPA). The diols were screened for estrogenic, androgenic, antiandrogenic, and antithyroid activities in reporter gene assays. Several of the low molecular weight asymmetric diols did not exhibit activity in any of the assays and thus have promise as potentially more sustainable alternatives to BPA.

The photoreduction of N-(p-benzoylbenzyl)-N,N,N-tri-n-butylammonium triphenyl-n-butylborate (1) and gallate (2) was studied using nano- and picosecond laser flash photolysis. An electron transfer reaction from the borate or the gallate counteranion to the excited triplet state of the benzophenone moiety (BP*3) was demonstrated. This reaction leads to the formation of benzophenone radical anion (6) and the boranyl radical, the latter of which dissociates rapidly to form butyl radical. The electron transfer rate was found to depend on the polarity of the solvent. In neat benzene, the short lifetime of the triplet obtained (300 ± 150 ps) indicates an intramolecular process and that the compounds exist as tight ion pairs. The addition of 1% MeCN increases the triplet lifetime up to 1.2 ns. The formation of a solvent-separated ion pair was suggested in this solvent mixture. However, in the polar solvent MeCN, 1 and 2 exist partially as free ions as determined by their dissociation constants. A diffusion-controlled intermolecular electron transfer process was shown in this solvent. The p-benzoylbenzyl radical (BPCH2 •), most likely formed by the C−N cleavage bond in the radical anion (6), was identified as an intermedate in the reaction pathway. After the initial electron transfer reaction, this produced tributylamine. The quantum yield obtained for the reaction of 1, 10-2 M in MeCN, is 0.5 ± 0.05. Triplet quenching as well as coupling of the radical anion (6) with the butyl radical deriving from decomposition of the borate was suggested to compete with the C−N cleavage reaction.

Several new tetraorganylborate salts have been synthesized and tested as coinitiators with 2,4‐diiodo‐6‐butoxy‐3‐fluorone (DIBF) for the photopolymerization of acrylic monomer mixtures. The rate of photopolymerization has been found to be a function of chemical structure of the borates. Stability, solubility, and reactivity of these borates as coinitiators for photopolymerization have been investigated. Diphenyldialkylborates have been found to be the best among the tested coinitiators. © 1996 John Wiley & Sons, Inc.