Ward Dale E, Beye Garrison E, Sales Marcelo, Alarcon Idralyn Q, Gillis H Martin, Jheengut Vishal
Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon SK S7N 5C9, Canada.
J Org Chem. 2007 Mar 2;72(5):1667-74. doi: 10.1021/jo0622532. Epub 2007 Jan 30.
The aldol reaction of tetrahydro-4H-thiopyranone with 1,4-dioxa-8-thiaspiro[4.5]decane-6-carboxaldehyde (I) gives four possible diastereomeric adducts (II). Aldol reactions of I with each of the diastereomers of II and their corresponding methoxymethyl ethers III via the Ti enolates were investigated. Using racemic reactants, reactions with II proceeded with high levels of mutual kinetic enantioselection (MKE) and double stereodifferentiation (DS) to give one of the eight possible bisaldol adducts. Similar reactions of III proceeded with low levels of MKE and DS and gave two bisaldol adducts, one from each of the possible combinations of enantiomeric reactants. By extension, 11 of the 20 possible diastereomers of the bisaldol adduct could be obtained selectively. These adducts are useful for polypropionate synthesis.
四氢-4H-硫代吡喃酮与1,4-二氧杂-8-硫杂螺[4.5]癸烷-6-甲醛（I）的羟醛反应生成四种可能的非对映异构加合物（II）。研究了I与II的每种非对映异构体及其相应的甲氧基甲基醚III通过钛烯醇盐进行的羟醛反应。使用外消旋反应物，与II的反应以高水平的相互动力学对映体选择性（MKE）和双重立体分化（DS）进行，得到八种可能的双羟醛加合物之一。III的类似反应以低水平的MKE和DS进行，并得到两种双羟醛加合物，分别来自对映体反应物的每种可能组合。通过扩展，可以选择性地获得双羟醛加合物的20种可能非对映异构体中的11种。这些加合物可用于聚丙酸酯的合成。
