6972-51-6Relevant academic research and scientific papers
Method of synthesizing 2,5-dimethyl phenylacetic acid through 2,5-dimethyl benzyl halide
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Paragraph 0037-0051, (2019/10/17)
The invention relates to the field of organic synthesis, in particular to a method of synthesizing 2,5-dimethyl phenylacetic acid through 2,5-dimethyl benzyl halide. The method comprises the followingsteps that 2,5-dimethyl benzyl halide reacts with magnesium to generate a Grignard reagent, namely, 2,5-dimethyl benzyl magnesium halide; 2,5-dimethyl benzyl magnesium halide reacts with paraformaldehyde to generate 2,5-dimethyl phenylethanol; and 2,5-dimethyl phenylethanol is oxidized into 2,5-dimethyl phenylacetic acid through NaClO and NaClO2 under a TEMPO or 4-OH TEMPO catalyst. The method has the advantages that in the synthesis process of 2,5-dimethyl phenylacetic acid, use of expensive noble metal catalysts and hypertoxic cyaniding reagents is avoided, the adopted reagents are environmentally friendly, the cost is lowered, the technology is simplified, the yield is high, the deficiencies in the prior art are overcome, and the method is suitable for large-scale industrial production.
Method for preparing 2,5-dimethylphenylacetic acid from 2,5-dimethylhalobenzene as raw material
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Paragraph 0042-0044; 0047-0049, (2019/11/04)
The invention relates to the field of organic synthesis, in particular to a method for preparing 2,5-dimethylphenylacetic acid by taking 2,5-dimethylhalobenzene as a raw material, which comprises thefollowing steps of: reacting 2,5-dimethylhalobenzene with magnesium to generate Grignard reagent 2,5-dimethylphenyl magnesium halide; 2,5-dimethylphenylmagnesium halide reacts with ethylene oxide to generate 2,5-dimethylphenylethanol; 2,5-dimethylphenylethanol is oxidized to 2,5-dimethylphenylacetic acid by NaClO and NaClO2 under TEMPO or 4-OH TEMPO catalyst. The invention has the advantages thatthe use of expensive noble metal catalysts and highly toxic cyanidation reagents is avoided in the synthesis process of 2,5-dimethylphenylacetic acid, the reagents used are environment-friendly, the cost is reduced, the process is simplified, the yield is higher, the defects of the prior art are overcome, and the method is suitable for large-scale industrial production.
A Phosphine-Catalyzed Novel Asymmetric [3+2] Cycloaddition of C,N-Cyclic Azomethine Imines with δ-Substituted Allenoates
Wang, De,Lei, Yu,Wei, Yin,Shi, Min
supporting information, p. 15325 - 15329 (2016/02/18)
Catalytic asymmetric [3+2] cycloadditions of C,N-cyclic azomethine imines with δ-substituted allenoates have been developed in the presence of (S)-Me-f-KetalPhos, affording functionalized tetrahydroquinoline frameworks in good yields with high diastereo- and good enantioselectivities under mild condition. The substrate scope has been also examined. This is the first time that δ-substituted allenoates have been applied as a δ,γ-C-C bond participated C 2 synthon in asymmetric synthesis. Another round: Catalytic asymmetric [3+2] cycloaddition of C,N-cyclic azomethine imines with δ-substituted allenoates have been developed in the presence of (S)-Me-f-KetalPhos, affording functionalized tetrahydroquinoline frameworks in good yields with high diastereo- and good enantioselectivities under mild conditions. This is the first example applying δ-substituted allenoates as C 2 synthons in asymmetric δ,γ-C-C bond formation.
Aromatic alkenylation using electrophilic organogallium reagent generated from allenylsilane and GaCl3
Kido, Yoshiyuki,Yonehara, Fumi,Yamaguchi, Masahiko
, p. 827 - 833 (2007/10/03)
Aromatic hydrocarbons are alkenylated with silylallene in the presence of GaCl3 at -90°C. Organometallic electrophiles generated from the allene and GaCl3 are the active species in this reaction. A modest level of ortho-selectivity is observed. While the silylallene reacts exclusively at the 2-position, 1,2-alkadiene reacts at the 1-position predominantly.
