Stereoselective synthesis of the insect growth regulator (S)-(+)-hydroprene through Suzuki–Miyaura cross-coupling

Dienolate Annulation Approach for Assembly of Densely Substituted Aromatic Architectures

“…Conjugated ester precursor of 32 was synthesized using a previously published method; spectral data matched published spectra. Product was purified with a gradient of 0–40% EtOAc in hexanes on silica gel, giving 32 as a yellow solid according to General Procedure D (47 mg, 0.1726 mmol, 40%, 80% brsm): 1 H NMR (500 MHz, CDCl 3 ) δ 7.71–7.65 (m, 1H), 7.46–7.40 (m, 2H), 7.19–7.12 (m, 1H), 6.96 (dd, J = 15.5, 2.3 Hz, 1H), 6.84 (dd, J = 8.7, 2.4 Hz, 2H), 4.24 (dtd, J = 8.7, 6.8, 1.9 Hz, 2H), 3.80–3.76 (m, 3H), 3.48–3.44 (m, 1H), 2.11 (t, J = 1.7 Hz, 4H), 1.29 (tt, J = 7.4, 1.8 Hz, 3H); 13 C NMR­{ 1 H} (126 MHz, CDCl 3 ) δ 14.2, 30.8, 55.3, 61.3, 76.6, 76.9, 77.1, 77.2, 78.0, 85.5, 112.2, 114.3, 122.9, 128.7, 129.2, 142.8, 149.1, 160.9, 165.2; FT-IR (NaCl Film) 3288, 3168, 3935, 2840, 1687, 1599, 1573, 1510, 1426, 1373, 1306, 1282, 1255, 1209, 1174, 1143, 1076, 1030, 946, 823, 766, 751, 694, 602 cm –1 ; HRMS (ESI+) m / z [M + H] + calcd for C 16 H 16 O 4 (M + H) + , 279.0991; found, 279.0988.…”

“…Product was purified with a gradient of 5−15% EtOAc in hexanes on silica gel, giving 20 as a white solid and from General Procedure A (50.7 mg, 0.1353 mmol, 85%): 1 H NMR (500 MHz, CDCl 3 ) δ 12.00 (s, 1H), 9.15 (s, 1H), 7.08 (s, 2H), 3.12 (tt, J = 11.4, 3.1 Hz, 1H), 1.90−1.74 (m, 6H), 1.53−1.45 (m, 4H), 1.26 (s, 9H); 13 C NMR{ 1 H} (125 MHz, CDCl 3 ) δ 161. 9, 161.3, 151.8, 135.7, 123.3, 117.1, 113.3, 112.47, 58.2, 39.3, 34.7, 34.4, 26.6, 26.6, 25.9, 22.2; 19 (S,E)-N-((2′-Azido-5′-hydroxy-[1,1′,3′,1″-terphenyl]-4′-yl)methylene)-2-methylpropane-2-sulfinamide (21). Product was purified with a gradient of 5−15% EtOAc in hexanes on silica gel, giving 21 as a white solid from General Procedure B (70 mg, 0.1672 mmol, 74%): 1 H NMR (400 MHz, CDCl 3 ) δ 11.79 (s, 1H), 8.47 (s, 1H), 7.60−7.43 (m, 8H), 7.39 (dt, J = 8.1, 1.6 Hz, 1H), 7.36−7.33 (m, 1H), 7.07 (s, 1H), 1.25 (s, 9H); 13 C NMR{ 1 H} (101 MHz, CDCl 3 ) δ 164.…”

Argon glow discharge plasma‐reduced palladium nanoparticles supported on activated carbon for Suzuki and Heck coupling reactions

“…The Suzuki coupling reaction is probably one of the most important, powerful and versatile methods for the formation of carbon-carbon bonds in the synthesis of natural products, agrochemicals and pharmaceutical intermediates, and in materials science. [1][2][3][4][5][6] Furthermore, the Heck coupling reaction of aryl halides with olefins has numerous applications for the synthesis of organic compounds. The transition metal palladium, used as a catalyst for Suzuki and Heck coupling reactions, has attracted considerable attention.…”