3-Benzyl-2-oxo-5-phenyl-2,3-dihydro-imidazole-1-carboxylic acid tert-butyl ester | 1026573-85-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 唑类
• 英文名称: 3-Benzyl-2-oxo-5-phenyl-2,3-dihydro-imidazole-1-carboxylic acid tert-butyl ester
• 英文别名: Tert-butyl 3-benzyl-2-oxo-5-phenylimidazole-1-carboxylate
• CAS: 1026573-85-2
• 化学式: C₂₁H₂₂N₂O₃
• 分子量: 350.417
• InChiKey: OEZFUMIVZUMWTR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.8
• 重原子数：
  26
• 可旋转键数：
  5
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.24
• 拓扑面积：
  49.8
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  3-Benzyl-2-oxo-5-phenyl-2,3-dihydro-imidazole-1-carboxylic acid tert-butyl ester 在 三氟乙酸 作用下， 生成 1,3-Dihydro-4-phenyl-1-(phenylmethyl)-2H-imidazol-2-one
  参考文献：
  名称：

  Regiospecific Functionalization of 1,3-Dihydro-2H-benzimidazol-2-one and Structurally Related Cyclic Urea Derivatives

  摘要：

  Methods for selectively protecting one of the degenerate nitrogen atoms of the cyclic urea derivatives 1,3-dihydro-2H-benzimidazol-2-one (6a), 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (11), 1,3-dihydro-2H-imidazo[4,5-b]quinolin-2-ones (20), 1,3-dihydro-2H-imidazo[4,5-c]pyridin-2-one (22), and 1,3-dihydro-4-phenyl-2H-imidazol-2-one (27) were developed. Heating these cyclic ureas with ethyl 2-pyridyl carbonate in the presence of a base in CH3CN at reflux or DMF at 100 degrees C cleanly provided the monoethoxycarbonyl derivatives 7a, 12, 21, 23, and 28, respectively. Alternatively, treatment of 6a with an excess of diethyl pyrocarbonate or di-tert-butyl dicarbonate afforded the bis-alkoxycarbonyl derivatives 8a and 8b, respectively, which underwent disproportionation to 7a and 7b upon heating with 1 mol equiv of 6a and K2CO3 in CH3CN at reflux. The regiochemistry of the introduction of alkoxycarbonyl groups to benzimidazol-2-one derivatives was not significantly influenced by an electron-withdrawing (CF3, 6b) or an electron-donating (OCH3, 6c) substituent at C-5 of the heterocyclic ring. However, the reaction was found to be sensitive to steric factors since a chlorine substituent ortho to one of the urea N atoms (6e) completely directed the alkoxycarbonyl moiety to the less sterically encumbered N atom, affording a single product (7f, 7g). Alkylation of 7a-g proceeded efficiently to provide products 10a-10ag after removal of the protecting group. Halogenation of monoprotected benzimidazol-2-one 7a occurred regiospecifically to give the monohalo derivatives 7h, 7i, and 7k, the identity of which were readily established from the characteristic chemical shift and spin coupling pattern in their 1H NMR spectra. A protecting group interchange strategy that took advantage of the distinctive chemical reactivities of the EtO(2)C and t-BuO(2)C protecting groups toward isopropylamine was developed that provided access to the isomerically substituted series of monohalo, mono-N-alkylated benzimidazol-2-ones 71 and 7m. The efficient derivatization of the unprotected N atom of these monoprotected cyclic urea derivatives was accomplished by treating with activated and unactivated halides in the. presence of K2CO3 or exposure to alcohols under Mitsunobu conditions. In several cases, mixtures of O- and N-alkylated products were produced which were readily separated by chromatography. Alkylation of 7h with activated halides, using K2CO3 in CH3CN at reflux, occurred without protecting group equilibration; however, a mixture of isomeric alkylated products was obtained when 7h was heated at 110 degrees C in DMF with cyclohexylmethyl bromide in the presence of K2CO3 as the base. Derivatization of 7h under Mitsunobu reaction conditions proceeded with retention of the topological substituent relationships. Subsequent removal of the alkoxycarbonyl moiety afforded monoalkylated cyclic urea derivatives.

  DOI：

  10.1021/jo00111a014
• 作为产物：
  描述：

  4-苯基-1,3-二氢-2H-咪唑-2-酮 在 4-二甲氨基吡啶 、 potassium carbonate 、 异丙胺 作用下， 以 四氢呋喃 、 N,N-二甲基甲酰胺 、 乙腈 为溶剂， 反应 21.17h， 生成 3-Benzyl-2-oxo-5-phenyl-2,3-dihydro-imidazole-1-carboxylic acid tert-butyl ester
  参考文献：
  名称：

  Regiospecific Functionalization of 1,3-Dihydro-2H-benzimidazol-2-one and Structurally Related Cyclic Urea Derivatives

  摘要：

  Methods for selectively protecting one of the degenerate nitrogen atoms of the cyclic urea derivatives 1,3-dihydro-2H-benzimidazol-2-one (6a), 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (11), 1,3-dihydro-2H-imidazo[4,5-b]quinolin-2-ones (20), 1,3-dihydro-2H-imidazo[4,5-c]pyridin-2-one (22), and 1,3-dihydro-4-phenyl-2H-imidazol-2-one (27) were developed. Heating these cyclic ureas with ethyl 2-pyridyl carbonate in the presence of a base in CH3CN at reflux or DMF at 100 degrees C cleanly provided the monoethoxycarbonyl derivatives 7a, 12, 21, 23, and 28, respectively. Alternatively, treatment of 6a with an excess of diethyl pyrocarbonate or di-tert-butyl dicarbonate afforded the bis-alkoxycarbonyl derivatives 8a and 8b, respectively, which underwent disproportionation to 7a and 7b upon heating with 1 mol equiv of 6a and K2CO3 in CH3CN at reflux. The regiochemistry of the introduction of alkoxycarbonyl groups to benzimidazol-2-one derivatives was not significantly influenced by an electron-withdrawing (CF3, 6b) or an electron-donating (OCH3, 6c) substituent at C-5 of the heterocyclic ring. However, the reaction was found to be sensitive to steric factors since a chlorine substituent ortho to one of the urea N atoms (6e) completely directed the alkoxycarbonyl moiety to the less sterically encumbered N atom, affording a single product (7f, 7g). Alkylation of 7a-g proceeded efficiently to provide products 10a-10ag after removal of the protecting group. Halogenation of monoprotected benzimidazol-2-one 7a occurred regiospecifically to give the monohalo derivatives 7h, 7i, and 7k, the identity of which were readily established from the characteristic chemical shift and spin coupling pattern in their 1H NMR spectra. A protecting group interchange strategy that took advantage of the distinctive chemical reactivities of the EtO(2)C and t-BuO(2)C protecting groups toward isopropylamine was developed that provided access to the isomerically substituted series of monohalo, mono-N-alkylated benzimidazol-2-ones 71 and 7m. The efficient derivatization of the unprotected N atom of these monoprotected cyclic urea derivatives was accomplished by treating with activated and unactivated halides in the. presence of K2CO3 or exposure to alcohols under Mitsunobu conditions. In several cases, mixtures of O- and N-alkylated products were produced which were readily separated by chromatography. Alkylation of 7h with activated halides, using K2CO3 in CH3CN at reflux, occurred without protecting group equilibration; however, a mixture of isomeric alkylated products was obtained when 7h was heated at 110 degrees C in DMF with cyclohexylmethyl bromide in the presence of K2CO3 as the base. Derivatization of 7h under Mitsunobu reaction conditions proceeded with retention of the topological substituent relationships. Subsequent removal of the alkoxycarbonyl moiety afforded monoalkylated cyclic urea derivatives.

  DOI：

  10.1021/jo00111a014

文献信息

• Regiospecific Functionalization of 1,3-Dihydro-2H-benzimidazol-2-one and Structurally Related Cyclic Urea Derivatives
  作者：Nicholas A. Meanwell、Sing Yuen Sit、Jinnian Gao、Henry S. Wong、Qi Gao、Denis R. St. Laurent、Neelakantan Balasubramanian

  DOI：10.1021/jo00111a014

  日期：1995.3

  Methods for selectively protecting one of the degenerate nitrogen atoms of the cyclic urea derivatives 1,3-dihydro-2H-benzimidazol-2-one (6a), 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one (11), 1,3-dihydro-2H-imidazo[4,5-b]quinolin-2-ones (20), 1,3-dihydro-2H-imidazo[4,5-c]pyridin-2-one (22), and 1,3-dihydro-4-phenyl-2H-imidazol-2-one (27) were developed. Heating these cyclic ureas with ethyl 2-pyridyl carbonate in the presence of a base in CH3CN at reflux or DMF at 100 degrees C cleanly provided the monoethoxycarbonyl derivatives 7a, 12, 21, 23, and 28, respectively. Alternatively, treatment of 6a with an excess of diethyl pyrocarbonate or di-tert-butyl dicarbonate afforded the bis-alkoxycarbonyl derivatives 8a and 8b, respectively, which underwent disproportionation to 7a and 7b upon heating with 1 mol equiv of 6a and K2CO3 in CH3CN at reflux. The regiochemistry of the introduction of alkoxycarbonyl groups to benzimidazol-2-one derivatives was not significantly influenced by an electron-withdrawing (CF3, 6b) or an electron-donating (OCH3, 6c) substituent at C-5 of the heterocyclic ring. However, the reaction was found to be sensitive to steric factors since a chlorine substituent ortho to one of the urea N atoms (6e) completely directed the alkoxycarbonyl moiety to the less sterically encumbered N atom, affording a single product (7f, 7g). Alkylation of 7a-g proceeded efficiently to provide products 10a-10ag after removal of the protecting group. Halogenation of monoprotected benzimidazol-2-one 7a occurred regiospecifically to give the monohalo derivatives 7h, 7i, and 7k, the identity of which were readily established from the characteristic chemical shift and spin coupling pattern in their 1H NMR spectra. A protecting group interchange strategy that took advantage of the distinctive chemical reactivities of the EtO(2)C and t-BuO(2)C protecting groups toward isopropylamine was developed that provided access to the isomerically substituted series of monohalo, mono-N-alkylated benzimidazol-2-ones 71 and 7m. The efficient derivatization of the unprotected N atom of these monoprotected cyclic urea derivatives was accomplished by treating with activated and unactivated halides in the. presence of K2CO3 or exposure to alcohols under Mitsunobu conditions. In several cases, mixtures of O- and N-alkylated products were produced which were readily separated by chromatography. Alkylation of 7h with activated halides, using K2CO3 in CH3CN at reflux, occurred without protecting group equilibration; however, a mixture of isomeric alkylated products was obtained when 7h was heated at 110 degrees C in DMF with cyclohexylmethyl bromide in the presence of K2CO3 as the base. Derivatization of 7h under Mitsunobu reaction conditions proceeded with retention of the topological substituent relationships. Subsequent removal of the alkoxycarbonyl moiety afforded monoalkylated cyclic urea derivatives.