Steric and Electronic Influences on the Diastereoselectivity of the Rh₂(OAc)₄-Catalyzed C−H Insertion in Chiral Ester Diazoanilides:  Synthesis of Chiral, Nonracemic 4-Substituted 2-Pyrrolidinones

Abstract

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N‐Phenyl‐1,2,3,4‐tetrahydroisoquinoline: An Alternative Scaffold for the Design of 17β‐Hydroxysteroid Dehydrogenase 1 Inhibitors

“…4‐Methoxy‐ N ‐(3‐methoxyphenethyl)aniline (14 f) : The crude compound was purified by column chromatography (eluent: from 0 to 40 % EtOAc in pet. ether) to give the product as a yellow oil (1.39 g, 59 %) which showed: [32] 1 H NMR (500 MHz, CDCl 3 ): δ =2.89 (2H, t, J =7.0 Hz, C H 2 CH 2 N), 3.36 (2H, t, J =7.0 Hz, CH 2 C H 2 N), 3.75 (3H, s, ArOCH 3 , aniline), 3.80 (3H, s, ArOCH 3 , phenethyl), 6.63 (2H, d, J =8.8 Hz, 2×ArCH, aniline), 6.74–6.83 (5H, m, 3×ArCH, phenethyl, 2×ArCH, aniline) and 7.23 (1H, t, J =7.8 Hz, ArCH, phenethyl) ppm. 13 C NMR (126 MHz, CDCl 3 ): δ =35.4 ( C H 2 CH 2 N), 46.2 (CH 2 C H 2 N), 55.2 (ArOCH 3 , phenethyl), 55.8 (ArOCH 3 , aniline), 111.7 (ArCH, phenethyl), 114.5 (ArCH, phenethyl), 114.8 (2×ArCH, aniline), 114.9 (2×ArCH, aniline), 121.1 (ArCH, phenethyl), 129.6 (ArCH, phenethyl), 140.8 (Ar C CH 2 ), 141.6 (ArCN), 152.4 (ArCO, aniline) and 159.7 (ArCO, phenethyl) ppm.…”

Air‐Stable, Sterically Hindered Ferrocenyl Dialkylphosphines for Palladium‐Catalyzed C—C, C—N, and C—O Bond‐Forming Cross‐Couplings.

“…13 6, Entry 1): 1 4 According to the general procedure A, 4-chloroanisole (73 mg, 0.51 mmol) reacted with benzylamine (68 mg, 0.63 mmol) using 1 mol % of Pd(dba) 2 , 2 mol % of Ph 5 FcP(t-Bu) 2 , and sodium tert-butoxide (60 mg, 0.63 mmol) in toluene at 100 °C for 4 h to give the title compound (100 mg, 93%) as a solid: 1 6, Entry 3): 6 According to the general procedure A, 4-chlorobenzonitrile (69 mg, 0.50 mmol) reacted with benzylamine (54 mg, 0.50 mmol) using 1 mol % of Pd(dba) 2 , 2 mol % of Ph 5 FcP(t-Bu) 2 , and sodium tert-butoxide (58 mg, 0.60 mmol) in toluene at 50 °C for 24 h to give the title compound (81 mg, 76%) as a solid: 1 6, Entry 4): 6 According to the general procedure A, chlorobenzene (58 mg, 0.51mmol) reacted with benzylamine (68 mg, 0.64 mmol) using 1 mol % of Pd(dba) 2 , 2 mol % of Ph 5 FcP(t-Bu) 2 , and sodium tert-butoxide (59 mg, 0.60 mmol) in toluene at 100 °C for 5 h to give the title compound (85 mg, 92%) as an oil. 1 6, Entry 5): 15 According to the general procedure A, 2chlorotoluene (66 mg, 0.52 mmol) reacted with benzylamine (68 mg, 0.64 mmol) using 1 mol % of Pd(dba) 2 , 2 mol % of Ph 5 FcP(t-Bu) 2 , and sodium tert-butoxide (60 mg, 0.63 mmol) in toluene at 100 °C for 4 h to give the title compound (99 mg, 96%) as a solid after recrystallization from hexane: 1 7, Entry 1): 16,17 According to the general procedure B, 7, Entries 2): 18 According to the general procedure B, 2chlorotoluene (73 mg, 0.58 mmol) reacted with n-hexylamine (80 µl, 0.61 mmol) using 1 mol % of Pd(dba) 2 , 2 mol % of Ph 5 FcP(t-Bu) 2 , and sodium tert-butoxide (59 mg, 0.60 mmol) in toluene at 70 °C for 8 h to give the title compound (102 mg, 92%) as a colorless oil: 1 7, Entry 3 and 4): 19,20 According to the general procedure B, 4-chlorobenzonitrile (69 mg, 0.50 mmol) reacted with n-hexylamine (80 µl, 0.60 mmol) using 1 mol % of Pd(dba) 2 , 2 mol % of Ph 5 FcP(t-Bu) 2 , and sodium tert-butoxide (58 mg, 0.60 mmol) in toluene at 70 °C for 8 h or at 100 °C for 13 h to give the title compound as a solid (79 mg, 78%).…”

Electronic Effects in Migratory Groups. [1,4]- versus [1,2]-Rearrangement in Rhodium Carbenoid Generated Bicyclic Oxonium Ylides

“…A few examples of this type are known wherein six-membered versus five-membered oxonium ylide formation (which is dependent on which diastereotopic oxygen out of the two possible oxygen atoms is involved in the oxonium ylide formation) decides the product distribution . The third factor that controls the product formation is the reaction conditions (i.e., solvent, temperature, and molar ratio of catalyst to substrate) . Our present study is related to the specificity due to substrate.…”