Stereospecific synthesis of racemic cis- and trans-6-trifluoromethylshikimic acids

New acrylate systems: derivatives of β-SF5-acrylic acid

“…For compound (2), the main isomer is the cis-isomer as both hydrogens are coupled to the SF 4 (F) group while the minor product has the trans structure; this is demonstrated by the lack of any coupling between the SF 4 (F) group and the adjoining cis H and by J ab coupling equals 10.94 Hz (cis) and 15 (trans). By comparison, the J ab coupling for cis-CF 3 CH¼CHC(O)OCH 2 CH 3 is 12.3 Hz [22].…”

(1R,4S,5R)-3-Fluoro-1,4,5-trihydroxy-2-cyclohexene-1-carboxylic acid: the fluoro analogue of the enolate intermediate in the reaction catalyzed by type II dehydroquinases

“…Methods for the introduction of fluorine into the shikimate nucleus have been investigated by several research groups with 2-fluoro, 15,17 3-fluoro, 18, 19 3,5-difluoro, 20 6-fluoro, 21-24 6,6difluoro 25 and 6-trifluoromethyl 26 derivatives having been (Ϫ)-Quinic acid 13 was smoothly protected as the cyclic bis-ketal 14 with concomitant protection of the C-1 carboxylate functionality as the methyl ester upon treatment with 2,3butanedione ketal 27 in an acidified mixture of trimethyl orthoformate and methanol at reflux (Scheme 3). The reaction afforded essentially a single product in high yield (79%), the ketal protecting group being selective for the vicinal transdiequatorial diol with a double anomeric effect controlling both ketal stereogenic centres.…”

Metal-Catalyzed Addition Polymers for 157 nm Resist Applications. Synthesis and Polymerization of Partially Fluorinated, Ester-Functionalized Tricyclo[4.2.1.02,5]non-7-enes

“…This is similar to some cycloadditions with furan in which high yields are observed after long reaction times at room temperature. 31 Further work is required to explain the reluctance of this fluorinated methacrylate to undergo cyclization with quadricyclane.…”