A New Method to Generate α-Aminoalkyl Radicals: Treatment of Methyl α-Amino Selenoesters with Hydride Reagents. Synthesis of 6-Azabicyclo[3.2.1]octanes by Radical Cyclization
A new method to generate α-aminoalkyl radicals and its application to the synthesis of 6-azabicyclo[3.2.1]octanes is described. α-Amino selenoesters on heating with Bu3SnH or (Me3Si)3SiH undergo decarbonylation of the initially formed acyl radical to give the corresponding α-amino radical which could be trapped intramolecularly with a double bond bearing an electron-withdrawing group.
A simple method of preparation of 7-alkyl-7-azabicyclo[2.2.1]heptanes
作者:Alfred Hassner、Anatoly M. Belostotskii
DOI:10.1016/0040-4039(95)00051-d
日期:1995.3
Action of triphenylphosphine - carbon tetrachloride on the trans-4-alkylaminocyclohexanols leads to 7-alkyl-7-azabicyclo[2.2.1]heptanes in the good yields. The starting aminoalcohols are easily available from the monoethylene ketal of 1,4-cyclohexanedione and primary amines in a four step process without isolation of intermediates.
A Simple and Efficient Synthesis of N-Substituted Cyclohex-3-enamines
作者:Mónica Álvarez-Pérez、José Marco-Contelles
DOI:10.1055/s-0029-1216989
日期:2009.11
A straightforward preparation of N-substituted cyclohex-3-enamines starting from the commercially available trans-4-aminocyclohexanol hydrochloride is described. Cyclohex-3-enamino-functionalized compounds have proven to be interesting intermediates in medicinal chemistry. The method here described is cheaper, more scalable and tolerant of a broader variety of functional groups than those found in
Chlorine Atom Transfer Radical 6-<i>exo</i>Cyclizations of Carbamoyldichloroacetate-Tethered Alkenes, Enol Acetates and α,β-Unsaturated Nitriles Leading to Morphans
CuI-mediated atomtransferradical cyclization of amino-tethered dichloromalonamides and electron-rich, electron-poor, and nonactivated double bonds is a useful methodology for the synthesis of 2-azabicyclo[3.3.1]nonanes. A study of the reaction conditions and the scope of the process is reported. Cyclopropane ring formation was observed from the resulting 1,3-dichlorides in some morphan substrates using
CuI 介导的原子转移自由基环化氨基连接的二氯丙二酰胺和富电子、缺电子和未活化的双键是合成 2-氮杂双环 [3.3.1] 壬烷的有用方法。报告了对反应条件和过程范围的研究。在一些使用 CuI、Pd 或 Zn 的吗啡底物中,从所得的 1,3-二氯化物观察到环丙烷环的形成。
Decarbonylative Radical Cyclization of α-Amino Selenoesters upon Electrophilic Alkenes. A General Method for the 6-Azabicyclo[3.2.1]octane Synthesis
alpha-Amino selenoester-tethered electronically poor alkenes on treatment with tributyltin hydride or TTMSS undergo intramolecular radical cyclization to provide 6-azabicyclo[3.2.1]octanes through 1-aminomethyl radical intermediates.