Preparation and oxidation of .alpha.-hydroxyaldehydes
Preparation and oxidation of .alpha.-hydroxyaldehydes
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DOI：
10.1021/jo00973a037
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发表时间：
1972-04
影响因子：
3.6
通讯作者：
P. Blumbergs;M. P. Lamontagne;J. I. Stevens
中科院分区：
文献类型：
--
作者：
P. Blumbergs;M. P. Lamontagne;J. I. Stevens
由相应的二氯甲基甲醇水解制得一系列α-羟基醛，产率33-62%。后一种化合物通过在-100 ℃下在四氢呋喃中将二氯甲基锂加到适当的酮中方便地制备。用冷的中性高锰酸钾氧化乙醇醛为相应的乙醇酸，产率为40- 55%。三氯甲基锂与适当的酮加成得到三氯甲基甲醇，水解反应可消除氯仿生成酮。氟里昂2将格氏试剂加到难获得的酮醛的肟上，生成羟醛肟，羟醛肟再用酸水解成相应的羟醛，产率很低。此外，-卤代醛的水解3 '4以低收率提供-羟基醛。
A series of-hydroxyaldehydes havebeen prepared in 33-62% yield via the hydrolysis of the corresponding dichloromethylcarbinols. The latter compounds were conveniently prepared by the addition of dichloromethyl-lithium to the appropriate ketone at—100 in tetrahydrofuran. The glycolic aldehydes were oxidized to the corresponding glycolic acids by cold, neutral potassium permanganatein yieldsof 40-55%. Hydrolysis of tri-chloromethylcarbinoLs, obtained by the addition of trichloromethyllithium and theappropriate ketone, resulted in the elimination of chloroform to regenerate the parent ketone.The syntheses of-hydroxyaldehydes havebeen severely limited in the past. Freon2 has added Gri-gnard reagents to the oximes of difficultly accessible-keto aldehydes to yield-hydroxyaldoximes which could then be hydrolyzed by acid to the corresponding-hydroxyaldehyde in low yields. Also, the hydrolysis of-haloaldehydes3’4 affords-hydroxyaldehydes in low yields.