New Heteroaromatic Azo Compounds Based on Pyridine, Isoxazole, and Benzothiazole for Efficient and Highly Selective Amidation and Mono-<i>N</i>-Benzylation of Amines under Mitsunobu Conditions
4,4′-Azopyridine (2c) is used in conjunction with triphenylphosphine for the efficient conversion of carboxylic acids into amides via Mitsunobu reaction with primary and secondary aliphatic and aromatic amines. The highly selective amidation of only primary aromatic amines with new heterogeneous azo compounds based on benzothiazole 2d and isoxazole 2e is also described. These azo compounds 2c–2e can also be applied for selective mono-N-benzylation of primary aromatic amines. The solid side product heteroaromatic hydrazines obtained under the developed Mitsunobu conditions are easily separated by simple filtration and can be reoxidized to azo compounds for further use.
Frustrated Lewis Pair Catalyzed Hydrogenation of Amides: Halides as Active Lewis Base in the Metal-Free Hydrogen Activation
作者:Nikolai A. Sitte、Markus Bursch、Stefan Grimme、Jan Paradies
DOI:10.1021/jacs.8b12997
日期:2019.1.9
reductant is introduced. The reaction proceeds via the hydrogen splitting by B(2,6-F2-C6H3)3 in combination with chloride as the Lewisbase. Density functional theory calculations support the unprecedented role of halides as active Lewisbase components in the frustratedLewispair mediated hydrogen activation. The reaction displays broad substrate scope for tertiary benzoic acid amides and α-branched carboxamides
aliphatic substrates for selective C(sp3)–H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C–H bonds. A number of late-stage C–H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)–H and C(sp3)–Hborylations enabling the method more general
A compound represented by the formula (I), an optically active isomer thereof, or a pharmaceutical acceptable salt thereof: wherein X represents CH or N; 1 represents a C1-C12 alkyl; R2 represents a hydrogen atom, or the like; R' represents a C1-C6 alkyl or the like; q represents 0 or an integer of 1 to 7; Y represents a C1-C6 alkyl or the like; p represents 0 or an integer of 1 to 5; R represents a 2,3-dihydroindolyl or the like, which is used for preventive and/or therapeutic treatment of a disease caused by tau protein kinase 1 hyperactivity such as a neurodegenerative diseases (e.g. Alzheimer disease).
A new concept for the meta‐selective borylation of aromatic amides is described. It has been demonstrated that while esters gave para borylations, amides lead to meta borylations. For achieving high meta selectivity, an L‐shaped bifunctional ligand has been employed and engages in an O⋅⋅⋅K noncovalent interaction with the oxygen atom of the moderately distorted amide carbonyl group. This interaction