Hypervalent Iodine Mediated Oxidative Cyclization of Acrylamide N-Carbamates to 5,5-Disubstituted Oxazolidine-2,4-diones

Abstract

A metal-free oxidative cyclization of N-Boc-acrylamides with (diacetoxyiodo)­benzene in acetic acid produced 5,5-disubstituted oxazolidine-2,4-diones with the formation of a C–O bond in moderate to excellent yields. In addition, the reaction was diastereospecific with N-Boc-2,3-dimethylacrylamides and proceeded with phenyl migration in the case of an N-Boc-2-phenylacrylamide to generate a 5-acetoxy-5-benzyloxazolidine-2,4-dione.

Chemistry of Isoeugenol and Its Oxidation Products: Mechanism and Kinetics of Isoeugenol as a Skin Sensitizer

“…1 H and 13 C NMR chemical shift calculations were performed to assign the relative configuration for C-7 and C-8 on the compounds 3a / 3b (Tables S2–S7) and C-7″ and C-8″ on 3a -DCYA adduct 4a (Tables S8–S10) using the CP3 () and DP4+ () probability analysis. , The ligand preparation (3D energy-minimized structure), conformational search, and geometry optimizations of the above compounds were performed using the procedure described earlier. , In brief, the 2D structures of compounds (7 R ,8 R )-7,4′-oxyneolignans ( 3 ), (7 S ,8 R )- 3 , (7″ R ,8″ R )-DCYA-adducts ( 4 ), and (7″ S ,8″ R )- 4 were drawn to include syn - 3 , anti - 3 , syn - 4 , and anti - 4 , respectively, in the 2D sketcher module of Maestro 12.6.144 (Schrödinger LLC, New York, NY, USA). The structures were prepared at physiological pH 7.4 with the LigPrep module implemented in the Schrödinger software (Schrödinger LLC, New York, NY, USA) using the OPLS3e force field .…”

Applications of Phenyliodine(III)diacetate in C−H Functionalization and Hetero‐Hetero Bond Formations: A Septennial Update

“…[129] The optimized reaction parameters are: PIDA (6 equiv), TFA (4 equiv), AcOH (2 equiv) in THF at rt. It's remarkable that paraoxidation of methoxytoluene (140) was selectively stopped at the aldehyde without going too far into the acid. Under the ideal reaction conditions, toluene, para-nitrotoluene, and parabromotoluene did not experience benzylic CÀ H oxidation.…”

“…The oxygenation of a benzylic C(sp 3 )À H bond with theNhydroxyamide ( 171) OÀ H bond was described by Li et al as a metal-free, room temperature method for creating C(sp 3 )À O bonds (173 and 175) with good functional group tolerance (Scheme 60). [140] The optimized reaction parameters are: PIDA (2 equiv.) in DCM at RT under argon.…”

“…as a metal‐free, room temperature method for creating C(sp 3 )−O bonds ( 173 and 175 ) with good functional group tolerance (Scheme 60). [140] The optimized reaction parameters are: PIDA (2 equiv.) in DCM at RT under argon.…”