4484-35-9Relevant articles and documents
PdII-Catalyzed Site-selective β- and γ-C(sp3)-H Arylation of Primary Aldehydes Controlled by Transient Directing Groups
Li, Yi-Hao,Ouyang, Yuxin,Chekshin, Nikita,Yu, Jin-Quan
supporting information, p. 4727 - 4733 (2022/04/07)
Pd(II)-catalyzed site-selective β- and γ-C(sp3)-H arylation of primary aldehydes is developed by rational design of L,X-type transient directing groups (TDG). External 2-pyridone ligands are identified to be crucial for the observed reactivity. By minimizing the loading of acid additives, the ligand effect is enhanced to achieve high reactivities of the challenging primary aldehyde substrates. Site selectivity can be switched from the proximate to the relatively remote position by changing the bite angle of TDG to match the desired palladacycle size. Experimental and computational investigations support this rationale for designing TDG to potentially achieve remote site-selective C(sp3)-H functionalizations.
Enantioselective Synthesis of N?H-Free 1,5-Benzothiazepines
Wang, Guojin,Tang, Yu,Zhang, Yu,Liu, Xiaohua,Lin, Lili,Feng, Xiaoming
supporting information, p. 554 - 557 (2017/01/18)
An enantioselective sulfa-Michael-cyclization reaction was developed for the synthesis of 1,5-benzothiazepines with versatile pharmacological activities. The reaction between 2-aminothiophenol and α,β-unsaturated pyrazoleamides gave direct access to N?H-free 1,5-benzothiazepines in the presence of a chiral N,N′-dioxide/Yb(OTf)3complex. Excellent enantioselectivities (up to 96 % ee) and high yields (up to 99 %) were obtained for a broad range of substrates under mild reaction conditions. This method provided a facile approach to the antidepressant drug (R)-(?)-Thiazesim.
Method for synthesizing alpha, beta-unsaturated acid by using formic acid and alkine
-
Paragraph 0024, (2016/10/27)
The invention relates to a method for synthesizing alpha, beta-unsaturated acid by using formic acid and alkine, in particular to a method for synthesizing alpha, beta-unsaturated acid by using formic acid and alkine under the effect of a nickel catalyst. The consumption of the catalyst is 0.01 to 2 mol percent of the quantity of a substrate substance; the consumption of estolide is 3 to 30 mol percent of the quantity of the substrate substance; the pressure of acetylene gas is 1 to 10 MPa; the reaction temperature is 25 to 100 DEG C; the reaction time is 5 to 12 hours. The method has the advantages that the existing alkine hydrocarboxylation defects are overcome; the use of toxic carbon monoxide gas does not needed; the reaction conditions of the whole process are mild; the efficiency is high; the selectivity is good; the method belongs to a method for preparing the alpha, beta-unsaturated acid with the advantages that the method conforms to green chemistry and has good application aspects; good industrial application prospects are realized.
