63224-15-7Relevant academic research and scientific papers
A Simple Aliphatic Diamine Auxiliary for Palladium-Catalyzed Arylation of Unactivated β-C(sp3)-H Bonds
Lou, Jiang,Wang, Quannan,He, Yuan,Yu, Zhengkun
supporting information, p. 4571 - 4584 (2018/10/25)
Palladium-catalyzed β-C(sp3)-H arylation of aliphatic acid derivatives was achieved by means of 2-dimethylaminoethylamine auxiliary as a directing group. The β-C(sp3)-H arylation reactions with aryl and heteroaryl iodides efficiently afforded the corresponding arylated hydrocinnamic acid derivatives. Direct β-C(sp3)-H alkynylation, and arene C?H arylation and alkynylation were also realized under the same or slightly modified conditions. The aliphatic diamine auxiliary in the products could be readily removed by methanol in the presence of BF3 ? OEt2. In comparison with the widely used bidentate nitrogen-containing directing groups, 2-dimethylaminoethylamine is a simple, cheap, readily available and removable, and atom-economical directing group for C?H functionalization. (Figure presented.).
Polarity-Tuning Derivatization-LC-MS Approach for Probing Global Carboxyl-Containing Metabolites in Colorectal Cancer
Bian, Xiqing,Li, Na,Tan, Binbin,Sun, Baoqing,Guo, Ming-Quan,Huang, Guoxin,Fu, Li,Hsiao, W. L. Wendy,Liu, Liang,Wu, Jian-Lin
, p. 11210 - 11215 (2018/10/02)
Carboxyl-containing metabolites (CCMs) widely exist in living systems and are the essential components for life. Global characteristics of CCMs in biological samples are critical for the understanding of physiological processes and the discovery for the onset of relevant diseases. However, their determination represents a challenge due to enormous polarity differences, structural diversity, high structural similarity, and poor ionization efficiency in mass spectrometry. Herein, 5-(diisopropylamino)amylamine (DIAAA) derivatization coupled with liquid chromatography-mass spectrometry (LC-MS) was developed for mapping the CCMs. With this methodology, the sensitivity was significantly enhanced. More importantly, the hydrophobicity of polar CCMs, amino acids, TCA cycle intermediates, and short-chain fatty acids and the hydrophilicity of low-polar CCMs, long-chain fatty acids, and bile acids were significantly increased, resulting in a remarkable separation efficiency for which 68 CCMs can be simultaneously determined. Furthermore, the polarity-tuning effect was confirmed to be induced by the different impacts of aliphatic chains and nitrogen atom in DIAAA, the latter existing as a cation in the acidic mobile phase, using different derivatization reagents. Finally, this derivatization method was utilized to hunt for the potential biomarkers in colorectal cancer (CRC) patients and 52 CCMs, related with several key metabolic pathways, including amino acids metabolism, TCA cycle, fatty acid metabolism, pyruvate metabolism, and gut flora metabolism were identified. This innovative polarity-tuning derivatization-LC-MS approach was proved to be a valuable tool for probing global metabolome with high separation efficiency and sensitivity in various biological samples.
4-Amino-2,1,3-benzothiadiazole as a Removable Bidentate Directing Group for the Pd(II)-Catalyzed Arylation/Oxygenation of sp2/sp3 β-C-H Bonds of Carboxamides
Reddy, Chennakesava,Bisht, Narendra,Parella, Ramarao,Babu, Srinivasarao Arulananda
, p. 12143 - 12168 (2016/12/23)
In this paper, we report 4-amino-2,1,3-benzothiadiazole (ABTD) as a new bidentate directing group for the Pd(II)-catalyzed sp2/sp3 C-H activation/functionalization of various aliphatic/alicyclic/aromatic carboxamide systems. The Pd(II)-catalyzed, ABTD-directed sp3 C-H arylation/acetoxylation of aliphatic- and alicyclic carboxamides afforded the corresponding β-C-H arylated/acetoxylated carboxamides. The Pd(II)-catalyzed, ABTD-directed sp3 C-H arylation of cyclobutanecarboxamide with different aryl iodides afforded the corresponding bis β-C-H arylated cyclobutanecarboxamides having all-cis stereochemistry with a high degree of stereocontrol. The Pd(II)-catalyzed, ABTD-directed arylation/benzylation/acetoxylation/alkoxylation of ortho C(sp2)-H bonds of various benzamides afforded the corresponding ortho C-H arylated/benzylated/oxygenated benzamides. The observed regio- and stereoselectivity in the Pd(II)-catalyzed, ABTD-directed arylation/benzylation of aliphatic/alicyclic carboxamides and benzamides were ascertained from the X-ray structures of representative compounds 5g (bis-β-C(sp3)-H arylated cyclobutanecarboxamide) and 7f (ortho C(sp2)-H arylated benzamide). A brief description on the efficiency, scope, and limitations of bidentate directing group ABTD is reported.
