Development of sustainable fluorous chemistry: the synthesis and characterization of fluorous ethers with nonafluoro-tert-butoxy groups

Abstract

Nonafluoro-t-butyl propyl (1), allyl (2), and propargyl (3) ethers as well as 1,2-bis(nonafluoro-t-butoxy)ethane (4), 1,3-bis(nonafluoro-t-butoxy)-propane (5), and 1,4-bis(nonafluoro-t-butoxy)-butane (6) were prepared by the reaction of sodium nonafluoro-t-butoxide (7) with the corresponding alkyl halides in good yields. Their fluorous partition coefficients and toxicity were also investigated. Computational studies have shown that 4, 5 and 6 exist in a monomeric form in MeOH-CF 3 C 6 F 11 and they likely aggregate to form oligomers in PhCH 3 -CF 3 C 6 F 11 . † Electronic supplementary information (ESI) available. See

Recycling and Delivery of Homogeneous Fluorous Rhodium Catalysts Using Poly(tetrafluoroethylene): “Catalyst-on-a-Tape”

“…These protocols are generally fluorous solvent free, greatly reducing the environmental organofluorine footprint. Furthermore, fluorous materials not based upon environmentally persistent fluorinated building blocks are becoming increasingly available. , The fluorous/organic solid/liquid biphase conditions do not yet match the retention of catalyst activity achievable with fluorous/organic liquid/liquid biphase conditions (Figures , ) . However, the incredibly diverse forms of PTFE as well as other fluoropolymers that are commercially available, particularly with respect to morphology and porosity, offer the possibility of extensive optimization and fine-tuning.…”

Fluorous ethers

“…The cytotoxicity of these fluorous ethers was shown to be lower than PFOA. 33 Perfluoroethers 48a-d were synthesised by the Williamson etherification of C 4 F 9 CH 2 CH 2 OH and alkyl bromides with various lengths of alkyl groups (Scheme 16). 24 49 was synthesised by preparing fluorous iodides from perfluoropropyl allyl ether and perfluorobutyl iodide in the presence of AIBN and aqueous Na 2 S 2 O 5 , followed by the heterogeneous palladium catalysed hydrogenation.…”

BODIPY Dyes Bearing Multibranched Fluorinated Chains: Synthesis, Structural, and Spectroscopic Studies

“…On the basis of this general framework, herein we present the synthesis and characterization of a small series of multibranched fluoroalkoxy‐substituted BODIPYs (Figure ). This molecular design multiplies the number of magnetically equivalent fluorine atoms in the molecule (27 or 54 F atoms per molecule) and guarantees a sustainable fluorous chemistry, producing degradation products with limited bioaccumulation . These synthesized BODIPYs not only differ in the position and number of fluorinated residues, but also in the extension of the conjugation length of the BODIPY core (Figure ).…”

“…This molecular design multiplies the number of magnetically equivalent fluorine atoms in the molecule (27 or 54 Fa toms per molecule) and guarantees as ustainable fluorous chemistry,p roducing degradation products with limited bioaccumulation. [16] These synthesized BODIPYs not only differ in the position and number of fluorinated residues, but also in the extension of the conjugation length of the BODIPY core ( Figure 1). In particular,c ompounds 1a and 1b are characterized by a para-perfluoroalkoxy-substituted phenylr ing in the meso position of the BODIPY core, with atotal of 27 magnetically equivalent fluorine atoms, whereas compounds 2a and 2b contain two perfluoro-tert-butoxy alkoxyr esidues boundt ot he boron atom, with at otal of 54 magnetically equivalent fluorine atoms.D erivatives 1b and 2b,w hich have am ore extended conjugation length than that of analogues 1a and 2a,t hanks to the introductionofs tyryl groups at the 3,5-positions,a re also characterized by an emission spectrumi nt he far-red region, which is more suitable for in vivo imaging.…”