179386-43-7Relevant articles and documents
Experiences with commercial production scale operation of dissolving metal reduction using lithium metal and liquid ammonia
Joshi,Sutton,Carver,Blanchard
, p. 997 - 1002 (2005)
The final step which generates free base in the synthesis of Sumanirole Maleate (PNU-95666E) consists of a cryogenic dissolving metal reduction using lithium metal and liquid ammonia. This chemistry was new to the Pfizer API production plant. Due to the hazards associated with the handling of lithium metal and ammonia gas at cryogenic reaction temperature, special challenges were encountered related to the design of the equipment, choice and handling of materials, operations, waste treatment, and both safety and economic issues. The topics discussed in this article include the use of Li instead of Na or K, impact of the choice of physical form of lithium metal, design of the lithium addition apparatus, and problems experienced during the addition. We also discuss techniques for addition of ammonia to the reactor, evaporation of ammonia from the reaction mixture, options for ammonia disposal, and internal reuse of ammonia. Comments on hazards for this reaction are also provided. It is hoped that this document will be of benefit to other professionals who may want to develop and scale-up dissolving metal reduction processes.
Scalable and safe synthetic organic electroreduction inspired by Li-ion battery chemistry
Peters, Byron K.,Rodriguez, Kevin X.,Reisberg, Solomon H.,Beil, Sebastian B.,Kawamata, Yu,Baran, Phil S.,Hickey, David P.,Klunder, Kevin,Gorey, Timothy J.,Anderson, Scott L.,Minteer, Shelley D.,Collins, Michael,Starr, Jeremy,Chen, Longrui,Udyavara, Sagar,Neurock, Matthew
, p. 838 - 845 (2019/04/30)
Reductive electrosynthesis has faced long-standing challenges in applications to complex organic substrates at scale. Here, we show how decades of research in lithium-ion battery materials, electrolytes, and additives can serve as an inspiration for achieving practically scalable reductive electrosynthetic conditions for the Birch reduction. Specifically, we demonstrate that using a sacrificial anode material (magnesium or aluminum), combined with a cheap, nontoxic, and water-soluble proton source (dimethylurea), and an overcharge protectant inspired by battery technology [tris(pyrrolidino)phosphoramide] can allow for multigram-scale synthesis of pharmaceutically relevant building blocks. We show how these conditions have a very high level of functional-group tolerance relative to classical electrochemical and chemical dissolving-metal reductions. Finally, we demonstrate that the same electrochemical conditions can be applied to other dissolving metal-type reductive transformations, including McMurry couplings, reductive ketone deoxygenations, and epoxide openings.
Enantioselective synthesis of (R)-Sumanirole using organocatalytic asymmetric aziridination of an α,β-unsaturated aldehyde
Nemoto, Tetsuhiro,Hayashi, Minami,Xu, Dashuang,Hamajima, Akinari,Hamada, Yasumasa
, p. 1133 - 1137 (2014/09/17)
Herein we report an enantioselective synthesis of (R)-Sumanirole wherein an organocatalytic asymmetric aziridination of 2-nitrocinnamaldehyde was the key step.
Synthesis and biological activities of (R)-5,6-dihydro-N,N-dimethyl-4H- imidazo[4,5,1-ij]quinolin-5-amine and its metabolites
Heier, Richard F.,Dolak, Lester A.,Duncan, J. Neil,Hyslop, Deborah K.,Lipton, Michael F.,Martin, Iain J.,Mauragis, Michael A.,Piercey, Montford F.,Nichols, Nanette F.,Schreur, Peggy J. K. D.,Smith, Martin W.,Moon, Malcolm W.
, p. 639 - 646 (2007/10/03)
The imidazoquinoline (R)-5,6-dihydro-N,N-dimethyl-4H-imidazo[4,5,1- ij]quinolin-5-amine [(R)3] is a potent dopamine agonist when tested in animals but surprisingly shows very low affinity in in vitro binding assays. When incubated with mouse or monkey liv
Synthesis of the Selective D2 Receptor Agonist PNU-95666E from D-Phenylalanine Using a Sequential Oxidative Cyclization Strategy
Romero, Arthur G.,Darlington, William H.,McMillan, Moses W.
, p. 6582 - 6587 (2007/10/03)
Compound 1 (PNU-95666E) is a selective and high-affinity agonist at the dopamine D2 receptor subtype and is of interest as a potential agent for the treatment of Parkinson's disease. Requiring a synthetic route amenable to scale-up, a synthesis