Synthesis of <i>N</i>-Oxyureas by Substitution and Cope-Type Hydroamination Reactions Using <i>O</i>-Isocyanate Precursors
作者:Meredith A. Allen、Ryan A. Ivanovich、Dilan E. Polat、André M. Beauchemin
DOI:10.1021/acs.orglett.7b03288
日期:2017.12.15
Oxy-carbamate O-isocyanate precursors facilitate access to synthetically valuable N-oxyureas via substitution with amines. This work exploits the reactivity of suitable O-isocyanate precursors, identified by a thorough study highlighting the different reactivity of isocyanate masking groups. This led to bench-stable O-isocyanate precursors, offering improved versatility in the synthesis of N-oxyureas, and
The carbamoylating agents carbamoylazides and carbamoyl cyanides (aka cyanoformamides) react with hydroxylamine in different ways, leading in the first case to N-hydroxyureas and, in the case of carbamoyl cyanides, to carbamoyl amidoxime derivatives. The synthetic procedure developed for the latter type of compound, which represents an interesting precursor for heterocyclic structures, allowed the
氨基甲酰基化剂氨基甲酰基叠氮化物和氨基甲酰基氰化物(又名氰基甲酰胺)以不同的方式与羟胺反应,在第一种情况下生成N-羟基脲,在氨基甲酰基氰化物的情况下,生成氨基甲酰基a肟肟衍生物。为后一种类型的化合物开发的合成方法代表了杂环结构的一种有趣的前体,可以高效地制备各种实例。在比较异丙基和苄基衍生物的实验值和计算出的13 C和15 N NMR化学位移值的基础上,提出了mid胺肟部分中双键的Z构型。
Correction to “Synthesis of <i>N</i>-Oxyureas by Substitution and Cope-Type Hydroamination Reactions Using <i>O</i>-Isocyanate Precursors”
作者:Meredith A. Allen、Ryan A. Ivanovich、Dilan E. Polat、André M. Beauchemin
DOI:10.1021/acs.orglett.2c02632
日期:2022.9.23
could not be obtained using the reported substitution strategy. Instead, primary amines underwent nucleophilic attack at the benzoate position to form the corresponding amide 6 by release of phenyl N-hydroxycarbamate 1a (Scheme 1). The NMR data for this product is in agreement with previous reports. (1) This finding was supported by the independent synthesis of benzoyloxy-urea 3i by acylation of hydroxy-urea