2216-69-5Relevant articles and documents
Heterocyclic seven-membered ring compounds, XXVIII. On 5-acetoxy- and 5-methoxy-1-benzothiepine and analogous 1-benzoxepines
Hofmann,Djafari
, p. 599 - 604 (1985)
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Fischer et al.
, p. 106 (1966)
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A Mild Heteroatom (O -, N -, and S -) Methylation Protocol Using Trimethyl Phosphate (TMP)-Ca(OH) 2Combination
Tang, Yu,Yu, Biao
, (2022/03/27)
A mild heteroatom methylation protocol using trimethyl phosphate (TMP)-Ca(OH)2combination has been developed, which proceeds in DMF, or water, or under neat conditions, at 80 °C or at room temperature. A series of O-, N-, and S-nucleophiles, including phenols, sulfonamides, N-heterocycles, such as 9H-carbazole, indole derivatives, and 1,8-naphthalimide, and aryl/alkyl thiols, are suitable substrates for this protocol. The high efficiency, operational simplicity, scalability, cost-efficiency, and environmentally friendly nature of this protocol make it an attractive alternative to the conventional base-promoted heteroatom methylation procedures.
Methylation with Dimethyl Carbonate/Dimethyl Sulfide Mixtures: An Integrated Process without Addition of Acid/Base and Formation of Residual Salts
Chan, Bun,Lui, Matthew Y.,Lui, Yuen Wai
, (2022/01/08)
Dimethyl sulfide, a major byproduct of the Kraft pulping process, was used as an inexpensive and sustainable catalyst/co-reagent (methyl donor) for various methylations with dimethyl carbonate (as both reagent and solvent), which afforded excellent yields of O-methylated phenols and benzoic acids, and mono-C-methylated arylacetonitriles. Furthermore, these products could be isolated using a remarkably straightforward workup and purification procedure, realized by dimethyl sulfide‘s neutral and distillable nature and the absence of residual salts. The likely mechanisms of these methylations were elucidated using experimental and theoretical methods, which revealed that the key step involves the generation of a highly reactive trimethylsulfonium methylcarbonate intermediate. The phenol methylation process represents a rare example of a Williamson-type reaction that occurs without the addition of a Br?nsted base.
Preparation method of naphthalene ring C marked α .
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Paragraph 0046-0048; 0056-0058; 0066-0068, (2021/10/05)
The invention discloses C labeled α - naphthalene acetic acid preparation method and belongs to the field of radioisotope C labeled compounds. C-labeled α - naphthylacetic acid preparation method, C radioisotope labeling is introduced on a naphthalene ring structure α -naphthol acid, C labeling site is in α-position. The method has the advantages that the reaction raw materials are easily available, the synthesis steps are high in yield, the total yield is more 60%, C marker isotopes are less in use amount, and waste is generated. The marker site α-position on the naphthalene ring is less likely to be metabolized compared to C-labeled branched acetic acid, and the synthesized C-labeled compound provides a better study of α -naphthoic acid in the environment.