Organic Reactions in Water: An Efficient Zinc-Mediated Stereoselective Synthesis of (<i>E</i>)- and (<i>Z</i>)-Trisubstituted Alkenes Using Unactivated Alkyl Halides
[reaction: see text] Treatment of the acetyl derivatives of the Baylis-Hillman adducts 3-hydroxy-2-methylene-alkanoates and 3-hydroxy-2-methylene-alkanenitriles with unactivated alkyl halides in the presence of Zn in saturated aqueous NH(4)Cl solution at room temperature afforded (2E)-2-substituted-alk-2-enoates in the first case and (2Z)-2-substituted-alk-2-enenitriles with high (Z)-selectivity in
Applications of Baylis–Hillman coupling products: a remarkable reversal of stereochemistry from esters to nitriles: a simple synthesis of (2E)-2-methylalk-2-en-1-ols and (2Z)-2-methylalk-2-enenitriles
作者:Deevi Basavaiah、Pakala K. S. Sarma
DOI:10.1039/c39920000955
日期:——
Reaction of methyl 3-acetoxy-2-methylenealkanoates with the reducing agent, lithium aluminium hydride (LAH): ethanol (1 : 1), provides (2E)-2-methylalk-2-en-1-ols, whereas, reaction of 3-acetoxy-2-methylenealkanenitriles with the same reagent provides (2Z)-2-methylalk-2-enenitriles in high yields.
Regioselective synthesis of poly-substituted thiophenes from Baylis–Hillman adducts
作者:Hyun Seung Lee、Se Hee Kim、Jae Nyoung Kim
DOI:10.1016/j.tetlet.2009.09.012
日期:2009.11
The reaction of Baylis–Hillman acetates and ethyl mercaptoacetate in the presence of DBU in DMF produced 2,3,4-trisubstituted tetrahydrothiophenes at room temperature as a diastereomeric mixture via the sequential SN2′ and Michael addition. Aromatization of tetrahydrothiophenes by DDQ oxidation produced 2,3,4-trisubstituted thiophenes in good yields.
在DBU中,在DBU中,Baylis–Hillman乙酸盐和巯基乙酸乙酯的反应通过连续的S N 2'和Michael加成反应,在室温下生成2,3,4-三取代的四氢噻吩,为非对映异构体混合物。通过DDQ氧化对四氢噻吩进行芳香化处理,可得到高产率的2,3,4-三取代噻吩。
Solid-Phase Synthesis of 3-Hydroxy-2-methylenealkanoates and Their Derivatives Using Polymer-Supported 2-(Phenylseleno)propanoate
A novel facile procedure for the solid-phase organic synthesis of 3-hydroxy-2-methylenealkanoates and their derivatives in good yields and with excellent purities using polymer-supported 2-(phenylseleno)propanoate is described.
A Mild and Efficient Stereoselective Synthesis of (Z)- and (E)-Allyl Sulfides and Potent Antifungal Agent, (Z)-3-(4-Methoxybenzylidene)thiochroman-4-one from Morita-Baylis-Hillman Acetates
A facile stereoselective synthesis of (Z)- and (E)-allyl sulfides has been accomplished from Morita–Baylis–Hillman acetates in one-pot by treatment with benzene thiol in the presence of catalytic amounts of 15% aqueous NaOH and TBAI in DMSO at room temperature. The method has been applied for the synthesis of (Z)-3-(4-methoxybenzylidene)thiochroman-4-one, a potent antifungal compound.