As an important bridge between the micro and macro material world, chemistry is one of the main methods and means for humans to understand and transform the material world. Quality Control of (S)-Butane-1,3-diol, The former is the study of compounds containing at least one carbon-hydrogen bonds.In a patent，Which mentioned a new discovery about 24621-61-2
A diastereoselective approach to (2R,5S)- and (2S,5S)-2-methyl-1,6-dioxaspiro[4.5]decane 1 and 1a is described. The route starts with an alkylation reaction among the cyclopentanone N,N-dimethylhydrazone 6 and the chiral iodides (R)-3 or (S)-3, derived from the enantiomers of ethyl beta-hydroxybutyrate, controlling the estereocenter at C-2 of the molecules. The alkylated products 7 and 7a were easily transformed into the 1,8-O-TBS-1,8-dihydroxy-5-nonanones 9 and 9a in four steps, and a subsequent stereoselective spiroketalization, in acidic media, afforded a Z:E mixture (1:2) of compounds 1 and 1a.
However, they have proven to be challenging because of the mutual inactivation of both catalysts. Each step is an elementary reaction. In my other articles, you can also check out more blogs about 24621-61-2
Reference：
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate