Atroposelective Construction of Nine‐Membered Carbonate‐Bridged Biaryls

Abstract

We herein demonstrated an efficient method for the atroposelective construction of nine-membered carbonate-bridged biaryls through vinylidene orthoquinone methide (VQM) intermediates. Diverse products with desirable pharmacological features were synthesized in satisfying yields and good to excellent enantioselectivities. In subsequent bioassays, several agents showed considerable antiproliferative activity via the mitochondrial-related apoptosis mechanism. Further transformations produced more structural diversity and may inspire new ideas for developing functional molecules.

A Stereodivergent–Convergent Chiral Induction Mode in Atroposelective Access to Biaryls via Rhodium-Catalyzed C–H Bond Activation

“…We focused on annulation between a biphenyl-2-boronic acid and a diazo reagent by virtue of dynamic kinetic transformation of the latter (Scheme c). On note, although dynamic kinetic transformation of coupling reagents has been recently reported in C–H activation, these are restricted to sterically hindered alkynes. ,, The most prominent feature of this system is the presence of a five-membered rhodafluorene intermediate containing two Rh–C bonds that are hardly distinguished by the chiral environment (Scheme c) . In this proof-of-concept study, the stereochemistry of the migratory insertion of two essentially indistinguishable Rh–C­(aryl) bonds and the relationship between the insertion-derived multiple chiral elements constitute a divergent–convergent chiral induction scenario.…”

Divergent Coupling of ortho-Alkynylnaphthols and Benzofurans: [4 + 2] Cycloaddition and Friedel–Crafts Reaction

“…1- (3,. 3f Prepared according to the reaction procedure I above, and the pure product 1a was isolated by flash chromatography column with V PE /V EA (50:1) as the eluent; 1 H NMR ( 500 1…”

“…1- (3,. 3f Prepared according to the reaction procedure I above, and the pure product 1d was isolated by flash chromatography column with V PE /V EA ( 50:1) as the eluent; 1 H NMR (500 MHz, CDCl 3 ) δ 8.13 (d, J = 8.7 Hz, 1H), 7.96 (s, 1H), 7.80 (d, J = 8.7 Hz, 1H), 7.77 (d, J = 8.9 Hz, 1H 6-(Benzo [d][1,3] 10 Prepared according to the reaction procedure I above, and the pure product 1e was isolated by flash chromatography column with V PE /V EA (40:1) as the eluent; 1 H NMR (500 MHz, CDCl 3 ) δ 8.08 (d,J = 8.7 Hz,1H),7.86 (s,1H),2H),3H),6.92 (d,J = 7.9 Hz, 1H), 6.08 (s, 1H), 6.02 (s, 2H), 1.47 (s, 9H).…”

“…(E)-1- (3,but-1-en-1-yl)naphthalen -2-yl-4-methylbenzenesulfonate (5b). Prepared according to the general procedure III above, and the pure product 5b was isolated by flash chromatography column with V PE /V EA (80:1) as the eluent; white solid (23.9 mg, 94% yield), mp 127−130 °C; C{H} NMR (126 MHz, CDCl 3 ) δ 152.…”

“…Prepared according to the general procedure III above, and the pure product 5b was isolated by flash chromatography column with V PE /V EA (80:1) as the eluent; white solid (23.9 mg, 94% yield), mp 127−130 °C; C{H} NMR (126 MHz, CDCl 3 ) δ 152. 9, 150.3, 145.9, 144.8, 143.7, 134.2, 133.6, 131.8, 131.4, 129.8, 129.0, 128.0, 127.6, 127.2, 126.43, 126.41, 126.1, 124.2, 122.0, 120.9, 120.0, 118.9, 111.6, 110.3, 34.9, 29.8, 21.3, 8.1 ppm;IR (KBr, cm −1 ): 3061, 2957, 2867, 2408, 1620, 1456, 1369, 1205 (Z)-1- (3,but-1-en-1-yl)naphthalen -2-yl-4-methylbenzenesulfonate (5i). Prepared according to the general procedure III above, and the pure product 5i was isolated by flash chromatography column with V PE /V EA (80:1) as the eluent; yellow oil (22.7 mg, 90% yield).…”