Convenient Formation of 4-Hydroxyalk-2-en-1-one Functionality via A Knoevenagel-type Carbon Chain Elongation Reaction of Aldehyde with 1-Arylsulfinylalkan-2-one
                                
                                    
                                        作者:Junzo Nokami、Kazuhide Kataoka、Kazuhiro Shiraishi、Masahiro Osafune、Iqbal Hussain、Shin-ichi Sumida                                    
                                    
                                        DOI:10.1021/jo001323g
                                    
                                    
                                        日期:2001.2.1
                                    
                                    A highly functionalized four-carbon unit, 4-hydroxyalk-2-en-1-one functionality [(RCH)-C-2(OH)CH=CHCOR1], was conveniently prepared by a reaction of an aldehyde ((RCH2CHO)-C-2) with a 1-(arylsulfinyl)alkan-2-one [ArS(O)CH2COR1] in the presence of diethylamine (Knoevenagel condition). Other functional groups, such as carbonyl and hydroxy groups, in both of the alkyl chains (R-1, R-2) did not prevent this reaction. This reaction was used to conveniently prepare (+/-)-(11E)-13-hydroxy-10-oxooctadec-11-enoic acid (14), having cytotoxic activity, and its analogues from undec-10-enoic acid in good yield.