Mono-deoxygenation of Nitroalkanes, Nitrones, and Heterocyclic N-Oxides by Hexamethyldisilane through 1,2-Elimination: Concept of “Counterattack Reagent”
摘要:
Transformation of secondary nitroalkanes to ketoximes was achieved in 40-73% yields by treatment of the corresponding nitronate anions with hexamethyldisilane. In this new mono-deoxygenation process, hexamethyldisilane acted as a "counterattack reagent". The conversion of nitrones to imines was also achieved in 82-88% yields by use of trimethylsilyllithium. Similarly, heterocyclic N-oxides were converted to the corresponding N-heterocycles in 73-86% yields. These deoxygenation processes presumably involve a 1,2-elimination.
Synthesis of Imines
<i>via</i>
Reactions of Benzyl Alcohol with Amines Using Half‐Sandwich (η
<sup>6</sup>
‐
<i>p</i>
‐cymene) Ruthenium(II) Complexes Stabilised by 2‐aminofluorene Derivatives
the complexes [Ru(η6‐p‐cymene)(Cl)(L2)], [Ru(η6‐p‐cymene)(Cl)(L3)] and [Ru(η6‐p‐cymene)(Cl)(L4)] revealed that the 2‐aminofluorene and p‐cymene moieties coordinate to ruthenium(II) in a three‐legged piano‐stool geometry. The synthesized complexes were used as catalysts for the dehydrogenative coupling of benzyl alcohol with a range of amines (aliphatic, aromatic and heterocyclic). The reactions were
一类新的半夹心的(η 6 - p -cymene)钌(II)配合物的2-氨基芴衍生物的[Ru(η支持6 - p -cymene)(CL)(L)](大号 = 2 - (( (9H-芴-2-基)亚氨基)甲基)苯酚(L 1),2-((((9H-芴-2-基)亚氨基)甲基)-3-甲氧基苯酚(L 2),1-((( 9H-芴-2-基)亚氨基)甲基)萘-2-醇(L 3)和N-((1H-吡咯-2-基)亚甲基)-9H-芴-2-胺(L 4))合成。所有化合物均通过分析和光谱技术(IR,UV-Vis,NMR)以及质谱进行了充分表征。的[Ru(η复合物的固态分子结构6 - p -cymene)(CL)(L 2)],[茹(η 6 - p -cymene)(CL)(L 3)]和[茹(η 6 ‐ p‐ cymene)(Cl)(L 4)]显示2-氨基芴和p苏木基部分以三足钢琴凳的几何形状与钌(II)配合。合成的络合物用作催
Carbonylation Access to Phthalimides Using Self-Sufficient Directing Group and Nucleophile
Herein we report a novel palladium-catalyzedoxidativecarbonylation reaction for the synthesis of phthalimides with high atom- and step-economy. In our strategy, the imine and H2O, which are generated in situ from the condensation of aldehyde and amine, serve as self-sufficient directing group and nucleophile, respectively. This method provides rapid access to phthalimides starting from readily available
A highly enantioselective synthesis of homoallylic amines, using allyltrimethoxysilane under Ag(I) catalytic conditions, has been developed. Among the chiral ligands investigated, a remarkable difference in the resulting Ag(I) complexes was observed. Under mild conditions and low catalyst loadings, homoallylamines were produced in high ee values (up to 80%) and good yields. The methodology can be further
已开发出在 Ag(I) 催化条件下使用烯丙基三甲氧基硅烷的高对映选择性合成高烯丙基胺。在所研究的手性配体中,观察到所得的 Ag(I) 配合物存在显着差异。在温和的条件和低催化剂负载下,以高 ee 值(高达 80%)和良好的产率生产高烯丙胺。该方法可以进一步扩展到醛亚胺的非对映选择性和对映选择性巴豆化。
Copper-catalyzed three component C S/C N coupling for the synthesis of trifluorothioacetamides
A copper-catalyzed three component C-S/C-N coupling reaction of imines with sulfur and CFC-113a was developed. The reaction involves amination and C = S double bond formation of CFC-113a, leading to biologically important trifluorothioacetamides. The method features efficient construction of trifluorothioacetyl moiety from cheap sulfur and CFC-113a, and safe disposal for environmentally persistent Freon.
Mono-deoxygenation of Nitroalkanes, Nitrones, and Heterocyclic <i>N</i>-Oxides by Hexamethyldisilane through 1,2-Elimination: Concept of “Counterattack Reagent”
作者:Jih Ru Hwu、Wen Nan Tseng、Himatkumar V. Patel、Fong Fuh Wong、Den-Nan Horng、Ben Ruey Liaw、Lung Ching Lin
DOI:10.1021/jo981054i
日期:1999.4.1
Transformation of secondary nitroalkanes to ketoximes was achieved in 40-73% yields by treatment of the corresponding nitronate anions with hexamethyldisilane. In this new mono-deoxygenation process, hexamethyldisilane acted as a "counterattack reagent". The conversion of nitrones to imines was also achieved in 82-88% yields by use of trimethylsilyllithium. Similarly, heterocyclic N-oxides were converted to the corresponding N-heterocycles in 73-86% yields. These deoxygenation processes presumably involve a 1,2-elimination.