Acetyl Chloride–Silver Nitrate–Acetonitrile: A Reagent System for the Synthesis of 2-Nitroglycals and 2-Nitro-1-Acetamido Sugars from Glycals
摘要:
A new reagent system comprising acetyl chloride, silver nitrate, and acetonitrile has been developed for the synthesis of 2-nitroglycals from the corresponding glycals. Under certain conditions, the formation of 2-nitro-1-acetamido sugars has also been observed. In addition, a few other non-carbohydrate-derived olefins also gave the corrresponding conjugated nitroolefins.
Asymmetric <i>N</i>-Hydroxyalkylation of Indoles with Ethyl Glyoxalates Catalyzed by a Chiral Phosphoric Acid: Highly Enantioselective Synthesis of Chiral <i>N,O</i>-Aminal Indole Derivatives
A method of SPINOL-derived chiralphosphoricacidcatalyzedasymmetric intermolecular N-hydroxyalkylation of multisubstituted indoles with ethyl glyoxalates is described in this report. This protocol provides an alternative, convenient, and direct strategy for efficient access to structurally unique α-chiral indole N,O-acyclic aminals with a broad substrate scope and good to excellent enantioselectivities
Diastereoselectivity in the triethylamine-catalyzed sulfa-Michael addition of thiols to nitroalkenes: kinetic and thermodynamic control
作者:Jiandong Wang、Ning Chen、Jiaxi Xu
DOI:10.1016/j.tet.2015.04.053
日期:2015.6
sulfa-Michael addition of nitroalkenes and thiols was investigated. The sulfa-Michael addition is kineticcontrol at the beginning and thermodynamiccontrol at the end for less bulky reactants. Thus, kinetic and thermodynamic-controlled adducts can be obtained as major products by controlling the reaction time in those cases. Linear nitroalkenes generally produce anti-adducts as major kinetic products due
Phosphonylpyrazoles from Bestmann−Ohira Reagent and Nitroalkenes: Synthesis and Dynamic NMR Studies
作者:Rajendran Muruganantham、Irishi Namboothiri
DOI:10.1021/jo902595e
日期:2010.4.2
also included Morita−Baylis−Hillman adducts of conjugated nitroalkenes with various electrophiles. Detailed dynamicNMRstudies were performed on the prototropic tautomerism exhibited by the phosphonylpyrazoles using CDCl3 and DMSO-d6 as solvents and 1H and 31P as the probe nuclei. These studies unraveled the existence of two tautomers in solution with a small energy difference but considerable barrier
1-重氮-2-氧代丙基膦酸二乙酯(Bestmann-Ohira试剂)作为硝基烯与环加成伙伴的应用已得到广泛研究。Bestmann-Ohira试剂与各种硝基烯烃(例如,碳环或杂环的一部分的β-取代的,α,β-二取代的和硝基乙烯)进行的碱介导反应通过室温下的一锅区域选择性反应提供了官能化的磷酸ny唑。高产。这些反应中使用的取代硝基烯烃还包括共轭硝基烯烃与各种亲电试剂的森田-贝利斯-希尔曼加合物。使用CDCl 3和DMSO- d 6作为溶剂,对膦酰基吡唑显示的质子互变异构进行了详细的动态NMR研究。1 H和31 P作为探针核。这些研究揭示了溶液中两种互变异构体的存在,它们的能量差很小,但对互变具有很大的障碍。
Zirconocene dichloride catalysed one-pot synthesis of pyrroles through nitroalkene-enamine assembly
作者:Sandeep Goyal、Jatinkumar K. Patel、Mukesh Gangar、Kapil Kumar、Vipin A. Nair
DOI:10.1039/c4ra09873k
日期:——
Zirconocene dichloride was found to be a highly efficient catalyst for the synthesis of multi-substituted pyrroles by a three-component, one-pot reaction.
锆二氯化物被发现是合成多取代吡咯烷的高效催化剂,通过三组分、一锅法反应。
The reaction of phenylethenes with NO2
作者:Duncan K. Bryant、Brian C. Challis、Jim Iley
DOI:10.1039/c39890001027
日期:——
Nitrogen dioxide reacts with phenylethenes to yield several products [PhCHO, PhCOCN, PhCO2H, PhCHCHNO2, PhCOCH2NO2, PhCH(OH)CH2NO2] that can be explained by radical addition of two NO2 molecules; the relevance of these reactions to the formation of nitropolycyclic aromatic hydrocarbons in the environment is discussed.
二氧化氮与苯乙烯反应生成几种产物[PhCHO,PhCOCN,PhCO 2 H,PhCH CHNO 2,PhCOCH 2 NO 2,PhCH(OH)CH 2 NO 2 ],这可以通过自由基加成两个NO 2分子来解释。讨论了这些反应与环境中硝基多环芳烃形成的相关性。