Facile optical resolution of tert-butanethiosulfinate by molecular complexation with (R)-BINOL and study of chiral discrimination of the diastereomeric complexes.
An important synthon, tert-butanethiosulfinate (2), has been effectively resolved by forming molecular complexes with (R)-2,2'-dihydroxy-1,1'-binaphthyl (BINOL, 3) in high enantioselectivity (>99 % ee). The present procedure represents the first example of the resolution of thiosulfinate. The mechanism of chiral discrimination is discussed in terms of molecular recognition based on IR and Xray analyses of the diastereomeric complexes during the resolution. In the less-soluble complex, (R)-3 and (R)-2 self-assembled as a linear supramolecule; however, in the more-soluble complex, (R)-3 and (S)-2 formed a simple bimolecular complex by one stronger hydrogen bond. Hydrogen bonding is the major driving force for effective resolution.
Liao
Jian
J
Union Laboratory of Asymmetric Synthesis, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.
Sun
Xiaoxia
X
Cui
Xin
X
Yu
Kaibei
K
Zhu
Jin
J
Deng
Jingen
J
D003461:Crystallography; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009281:Naphthalenes / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism; D013451:Sulfonic Acids / Q000737:chemistry*
D009281:Naphthalenes; C475744:S(-)2,2'-dihydroxy-1,1'-binaphthyl; D013451:Sulfonic Acids; C419650:tert-butyl tert-butanethiosulfinate