Carbonyl Oxide Chemistry. 6.¹ N-(Hydroperoxyalkyl)keto Nitrones and α-Oxime Ether Hydroperoxides via Disubstituted Carbonyl Oxides and Oximes

Axially Chiral Enamides: Substituent Effects, Rotation Barriers, and Implications for their Cyclization Reactions

“…This procedure involved preparing acetamides 5a – j or 2-chloroacetamides 5k – m via an iron-mediated rearrangement of literature oximes. ,− These acetamides were then alkylated with alkyl halides to furnish the enamides 4b , 4d – i , 7a – d , 8a , 8b , 8d , 8e , 13b – d , 14 , 15 , 25a , 26a , 27a , 27b , 27d , 28 .…”

“…Synthesis of Known Compounds by Literature Methods. Butan-2-one oxime, 86 3-methylbutan-2-one oxime, 87 isobutyraldehyde oxime, 88 2-methyl-1-tetralone oxime, 89 2-methyl-1-phenylpropan-1one oxime, 39 cyclohexyl(phenyl)methanone oxime, 39 2-phenylcyclohexanone oxime, 90 2,2,6-trimethylcyclohexanone oxime, 91 2,4-dimeth-yl-3-pentanone oxime, 92 and N-benzyl-N-(prop-1-en-2-yl)acetamide (4a) 32 were prepared by literature procedures and exhibited 1 H and 13 C NMR spectroscopic details identical to those previously reported. 1 H NMR was used to check the purity of all the compounds.…”

“…N-(2-Methylprop-1-enyl)acetamide (5d, X = H, R 1 = H, R 2 = R 3 = Me). 95 Conditions: isobutryaldehyde oxime 88 (2.00 g, 22.9 mmol), acetic acid (3.94 mL, 68.9 mmol), acetic anhydride (6.50 mL, 68.9 mmol), iron powder (2.56 g, 45.3 mmol), and anhydrous toluene (30 mL). The crude product was purified by column chromatography (pet.…”

“…Yield 3.17 g (56%); 5:3 ratio of isomers; white crystalline solid; mp 64−66 °C; R f 0.60 (pet. ether:EtOAc, 1:1); IR υ max (film)/ cm −1 3242, 2972, 1641; 1 H NMR δ H (CDCl 3 , 400 MHz) 6.15 (1H, s, minor), 6.07 (1H, s, major), 2.90−2.98 (1H, m), 2.08 (3H, s, major), 1.88 (3H, s, minor), 1.77 (3H, s major and minor), 1.67 (3H, s, minor), 1.61 (3H, s, major), 0.97 (6H, d, J = 7.0 Hz, minor), 0.95 (6H, d, J = 7.0 Hz, major); 13 37 Conditions: 2-methyl-1tetralone oxime 88 (980 mg, 5.6 mmol), acetic acid (0.97 mL, 16.8 mmol), acetic anhydride (0.62 mL, 16.8 mmol), iron powder (0.63 g, 72.6 mmol), and anhydrous toluene (20 mL). The crude product was purified flash chromatography (5:1 hexane:EtOAc).…”

A Simple One-Pot Synthesis of Functionalized 1,2-Oxazin-6-ones

“…8 In connection with a program on the preparation and use of organic peroxides, 9 we now report a new synthetic approach to functionalized 1,2-oxazin-6-ones 4 starting from 2-methoxyfurans 1 via N-(hydroperoxyalkyl)keto nitrones 2. The latter compounds, which were previously unknown, have recently been prepared by dye-sensitized photooxygenation of 2-methoxyfurans 1, unsubstituted at C-4, in the presence of aliphatic aldoximes (Scheme 1), 10 according to a procedure reported for N-(hydroperoxyalkyl)aldo nitrones. 11 Reduction of 2 with diethyl sulfide quantitatively led to the corresponding ketoximes 3.…”