Formal and improved synthesis of enantiopure chiral methanol
摘要:
[D2]Methanol was converted to the carbamate derived from 2,2,6,6-tetramethylpiperidine. It was metalated with s-BuLi/TMEDA at -78 C with a high primary kinetic isotope effect to give an n.-oxymethyllithium, which was silylated with chlorodimethylphenylsilane. The silylmethyl carbamate formed was lithiated and borylated with the borate derived from tert-butanol and (R,R)-1,2-dicyclohexylethane-7,2-diol to give diastereomeric boronates, which were separated by preparative HPLC and can in principle be converted to enantiopure chiral methanols. Thus, both enantiomers are easily accessible in nine linear steps. (C) 2008 Elsevier Ltd. All rights reserved.
Formal and improved synthesis of enantiopure chiral methanol
摘要:
[D2]Methanol was converted to the carbamate derived from 2,2,6,6-tetramethylpiperidine. It was metalated with s-BuLi/TMEDA at -78 C with a high primary kinetic isotope effect to give an n.-oxymethyllithium, which was silylated with chlorodimethylphenylsilane. The silylmethyl carbamate formed was lithiated and borylated with the borate derived from tert-butanol and (R,R)-1,2-dicyclohexylethane-7,2-diol to give diastereomeric boronates, which were separated by preparative HPLC and can in principle be converted to enantiopure chiral methanols. Thus, both enantiomers are easily accessible in nine linear steps. (C) 2008 Elsevier Ltd. All rights reserved.