1070-62-8Relevant articles and documents
Bailey,Carpenter
, p. 1252 (1964)
Synthesis of protected α-amino acids: Via decarboxylation amination from malonate derivatives
Dai, Qipu,Fu, Hui,Hu, Changwen,Li, Peihe,Li, Xiaoying,Wang, Zheng
, p. 4439 - 4446 (2020/10/20)
A general and efficient strategy for the synthesis of protected α-amino acids is reported. The method uses malonate derivatives as the starting materials and Cs2CO3 as a base at 60 degrees, giving α-amino acid derivatives in moderate yields by releasing CO2. This methodology shows broad substrate scope (primary and secondary acids), excellent functional group tolerance and high efficiency to give the desired products under mild reaction conditions. It also allows the construction of β and γ-amino acids and other unnatural products.
Transition-Metal-Free carboxylation of organozinc reagents using CO 2 in DMF solvent
Kobayashi, Koji,Kondo, Yoshinori
supporting information; experimental part, p. 2035 - 2037 (2009/09/08)
An efficient process for the carboxylation of functionalized organozinc reagents with CO2 under transition-metal-free conditions was developed by employing DMF solvent in the presence of LICl.
A New Class of Linear Tetrapyrroles: Acetylenic 10,10a-Didehydro-10a-homobilirubins
Tu, Bin,Ghosh, Brahmananda,Lightner, David A.
, p. 8950 - 8963 (2007/10/03)
Novel bilirubin analogues with dipyrrinones conjoined to an acetylene rather than a methylene group were synthesized and examined spectroscopically. Despite the increased separation of the dipyrrinones forced by replacing a -CH2- by a -C≡C- unit, molecular dynamics calculations show that, like bilirubin, they may still engage in intramolecular hydrogen bonding to carboxylic acid groups when the propionic acid chains are slightly lengthened, e.g., butanoic acids. Unlike bilirubin, however, which is bent in the middle and has a ridge-tile shape, the acetylene orients the attached dipyrrinones along a linear path, and intramolecular hydrogen bonding preserves a twisted linear molecular shape. The extended planes of the dipyrrinones intersect along the -C≡C- axis at an angle of 136° for the conformation stabilized by intramolecular hydrogen bonding in the bis-butyric acid rubin (lb). With shorter acid chains (propionic), only one CO2H can engage an opposing dipyrrinone in intramolecular hydrogen bonding, and in this energy-minimum conformation of the linear pigment 1a, the intersection of the extended planes of the dipyrrinones has an angle of 171°. Spectroscopic evidence for such linearized and twisted structures was found in the pigments' NMR spectral data and their exciton UV-vis and induced circular dichroism spectra.
