85416-73-5Relevant articles and documents
Multistep continuous-flow synthesis of (R)- and (S)-rolipram using heterogeneous catalysts
Tsubogo, Tetsu,Oyamada, Hidekazu,Kobayashi, Shu
, p. 329 - 332 (2015)
Chemical manufacturing is conducted using either batch systems or continuous-flow systems. Flow systems have several advantages over batch systems, particularly in terms of productivity, heat and mixing efficiency, safety, and reproducibility. However, fo
Enantioselective Synthesis of Pyroglutamic Acid Esters from Glycinate via Carbonyl Catalysis
Ma, Jiguo,Zhou, Qinghai,Song, Guanshui,Song, Yongchang,Zhao, Guoqing,Ding, Kuiling,Zhao, Baoguo
, p. 10588 - 10592 (2021/04/06)
Direct α-functionalization of NH2-free glycinates with relatively weak electrophiles such as α,β-unsaturated esters still remains a big challenge in organic synthesis. With chiral pyridoxal 5 d as a carbonyl catalyst, direct asymmetric conjugated addition at the α-C of glycinate 1 a with α,β-unsaturated esters 2 has been successfully realized, to produce various chiral pyroglutamic acid esters 4 in 14–96 % yields with 81–97 % ee's after in situ lactamization. The trans and cis diastereomers can be obtained at the same time by chromatography and both of them can be easily converted into chiral 4-substituted pyrrolidin-2-ones such as Alzheimer's drug Rolipram (11) with the same absolute configuration via tert-butyl group removal and subsequent Barton decarboxylation.
Efficient synthesis of (?)-(R)- and (+)-(S)-rolipram
Kaur, Ramandeep,Pandey, Satyendra Kumar
, p. 4333 - 4335 (2017/10/17)
A novel, efficient and protecting group free enantioselective synthetic approach of (?)-(R)-1 and (+)-(S)-rolipram 2 is described employing the organocatalyzed asymmetric Michael addition, Henry condensation, Wittig olefination and reductive lactamization
