202925-92-6Relevant articles and documents
Alkene synthesis by photocatalytic chemoenzymatically compatible dehydrodecarboxylation of carboxylic acids and biomass
Nguyen, Vu T.,Nguyen, Viet D.,Haug, Graham C.,Dang, Hang T.,Jin, Shengfei,Li, Zhiliang,Flores-Hansen, Carsten,Benavides, Brenda S.,Arman, Hadi D.,Larionov, Oleg V.
, p. 9485 - 9498 (2019/10/11)
Direct conversion of renewable biomass and bioderived chemicals to valuable synthetic intermediates for organic synthesis and materials science applications by means of mild and chemoselective catalytic methods has largely remained elusive. Development of artificial catalytic systems that are compatible with enzymatic reactions provides a synergistic solution to this enduring challenge by leveraging previously unachievable reactivity and selectivity modes. We report herein a dual catalytic dehydrodecarboxylation reaction that is enabled by a crossover of the photoinduced acridine-catalyzed O-H hydrogen atom transfer (HAT) and cobaloxime-catalyzed C-H-HAT processes. The reaction produces a variety of alkenes from readily available carboxylic acids. The reaction can be embedded in a scalable triple-catalytic cooperative chemoenzymatic lipase-acridine-cobaloxime process that allows for direct conversion of plant oils and biomass to long-chain terminal alkenes, precursors to bioderived polymers.
Cobalt-catalyzed carbon-carbon bond formation: Synthesis and applications of enantiopure pyrrolidine derivatives[1]
Hsu, Shih-Fan,Ko, Chih-Wei,Wu, Yao-Ting
, p. 1756 - 1762 (2011/09/20)
In the presence of cobalt catalysts and tetramethylethylenediamine (TMEDA), the iodine atom in (S)-2-(iodomethyl)pyrrolidines was replaced by an aryl or an alkynyl group from the corresponding Grignard reagent, and the coupling products were obtained in good to excellent yields (16 examples; 75-94% yields). The scope and limitations of this protocol were examined. The stereochemistry of the pyrrolidines was unaffected by the reaction conditions. The coupling products are important building blocks of phenanthroindolizidine alkaloids. Palladium-catalyzed formal [4+2] cycloaddition of 2,2′-diiodobiphenyl with the thus-generated (S)-2-(3-trimethylsilyl-2-propynyl)pyrrolidine gave a good yield of the desilylated phenanthrene, which was then converted into unnatural (+)-(S)-tylophorine by the Pictet-Spengler cyclization. Copyright
In situ trapping of Boc-2-pyrrolidinylmethylzinc iodide with aryl iodides: Direct synthesis of 2-benzylpyrrolidines
Massah, Ahmad Reza,Ross, Andrew J.,Jackson, Richard F. W.
experimental part, p. 8275 - 8278 (2011/03/18)
Addition of (S)-(+)-tert-butyl 2-(iodomethyl)pyrrolidine-1-carboxylate to activated zinc, aryl halides, and a catalyst derived from Pd2(dba) 3 (2.5 mol %) and SPhos (5 mol %) in DMF allows trapping of the corresponding organozinc rea
Collagen cross-links: Synthesis of pyridinoline, deoxypyridinoline and their analogues
Adamczyk, Maciej,Johnson, Donald D.,Reddy, Rajarathnam E.
, p. 63 - 88 (2007/10/03)
An efficient chiral synthesis of (S,S)-(-)-3g, a key intermediate for the preparation of collagen cross-links pyridinoline (Pyd, 1) and deoxypyridinoline (Dpd, 2) was achieved from (4S)-5(tert-butoxy)-4-[(tert- butoxycarbonyl)amino]-5-oxopentanoic acid (21b). Quaternization of (S,S)-(- )-3g with iodide (2S, 5R)-(+)-4a followed by hydrolysiS provided a first chiral synthesis of natural (+)-Pyd (1). 1-(2S)-(+)-Pyd (1) was also synthesized from (S,S)-(-)-3g and iodide (2S, 5S)-(+)-4a. Similarly, quaternization of (S,S)-(-)-3g with iodide (2S)-(-)-4b, which was prepared from (2S)-(-)-6-amino-2[(tert-butoxycarbonyl)amino]hexanoic acid (31) in three steps, followed by hydrolysis afforded natural (+)-Dpd (2) in 5.3% overall yield. Also, the synthesis of racemic Dpd [(±)-2] and a variety of its analogues is presented.
