Diels‐Alder Reaction of β‐Fluoro‐β‐nitrostyrenes. Synthesis of Mono‐fluorinated Six‐Membered Derivatives

Abstract

The Diels-Alder reaction of-fluoro-nitrostyrenes with some linear dienes was investigated. A number of monofluorinated [4+2]-cycloadducts was prepared in up to 90 % yield. The kinetics of [4+2]-cycloaddition to 2,3-dimethyl-1,3butadiene was studied in detail to reveal substituent effect and

Diels-Alder Reaction of β-Fluoro-β-nitrostyrenes with Cyclic Dienes

“…Chemical shifts for 1 H NMR spectroscopic data were referenced to internal tetramethylsilane (δ = 0.0 ppm) and the residual solvent resonance (δ = 7.26 ppm); chemical shifts for 13 C NMR spectroscopic data were referenced to residual solvent resonance (δ = 77.16 ppm); chemical shifts for 19 F NMR spectroscopic data were referenced to PhCF3 (δ = -63.72 ppm). Data are reported as follows: chemical shift, integration multiplicity (s = singlet, d = doublet, t = triplet, q = quadruplet, qui = quintet, sext = sextet, sept = septet, br = board, m = multiplet, dd = doublet of doublets, ddd = doublet of doublet of doublets) and coupling constants (Hz).…”

Diels-Alder Reaction of β-Fluoro-β-nitrostyrenes with Cyclic Dienes

“…2-Fluoro-3-(4-nitrophenyl)bicyclo[2.2.1]hepta-2,5-diene (6). 0.034 g, 77 % yield; yellow oil; 1 H NMR (400 MHz, CDCl3) δ = 2.28 (ddd, J = 6.5, 4.7, 1.9 Hz, 1H), 2.41 -2.46 (m, 1H), 3.47 -3.53 (m, 1H), 3.88 -3.94 (m, 1H), 6.95 (dd, J = 4.5, 3.1 Hz, 1H), 7.05 (dt, J = 4.6, 2.2 Hz, 1H), 7.47 -7.56 (m, 2H), 8.16 -8.20 (m, 2H) ppm; 19 F NMR (376 MHz, CDCl3): δ = -110.34 (s) ppm. The analysis of the sample was consistent with the previously reported data [15a]…”

One-pot and metal-free synthesis of 3-arylated-4-nitrophenols via polyfunctionalized cyclohexanones from β-nitrostyrenes

“…On the other hand, nitroalkenes possess an electron-deficient double bond, and hence, they serve as an excellent Michael acceptor and dienophile [12][13][14][15][16][17][18][19]. When β-nitrostyrene (1, Ar = Ph) is subjected to the Diels-Alder reaction, a C2 unit possessing a nitro group and an aryl group at the vicinal position is incorporated into the products.…”