Sodium dithionite initiated regio- and stereoselective radical addition of polyfluoroalkyl iodide with norbornene analogs

Add time:07/18/2019    Source:sciencedirect.com

Sodium dithionite initiated free-radical addition of polyfluoroalkyl iodides (2m–2s) with norbornene 1a and its derivatives, such as norbornene-2-carboxylates 1b and 1c, and norbornene-2-carboxylic acids 1d and 1e was investigated. In all the cases, the addition of RF group was stereoselectively delivered at exo-position and the predominant configuration of products was trans. Under the similar condition, norbornene-2-carboxylic ethyl ester 1b reacted with 2p to give 6-exo-RF-5-endo-iodo adduct 3bp and 5-exo-RF-6-endo-iodo adduct 5bp in the ratio of 4:1. While 1c, which has a heavy crowded group in the 2-endo-position, gave 6-exo-RF-5-endo-iodo adduct 3cp and polyfluoroalkylated product 4cp retaining the trans-configuration and the exo-orientation of RF group. The fluoroalkylation–lactonization reaction occurred in the reaction of norbornene-2-endo-carboxylic acids 1d and 1e with polyfluoroalkyl iodides to afford the corresponding fluoroalkylated γ-lactone products (7dp–7ds, and 7em–7er). The configuration of the products was further confirmed by 2D NMR and X-ray diffraction analyses for the first time.

We also recommend Trading Suppliers and Manufacturers of ETHYL 5-NORBORNENE-2-CARBOXYLATE (MIXTURE OF ENDO AND EXO) (cas 10138-32-6). Pls Click Website Link as below: cas 10138-32-6 suppliers

Prev:The synthesis of fluorinated endcaps: Part 2. Preserving the endo,endo configuration in the monohydrolysis of 7-fluorinated nadic diesters
Next:Synthesis and structural characterization of dinuclear cerium(III) and erbium(III) complexes of nicotinic acid or 2-aminobenzoic acid)