24539-56-8Relevant articles and documents
Synthesis method of high-purity phthalic acid n-pentyl isoamyl ester
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Paragraph 0021-0024; 0033-0035, (2019/06/27)
The invention discloses a synthesis method of high-purity phthalic acid n-pentyl isoamyl ester. The method is characterized in that pyridine is adopted as alkali, and phthalic anhydride is adopted tobe reacted with n-pentanol to obtain an intermediate I; heating backflowing reaction is conducted on the prepared intermediate I and thionyl chloride, and intermediate II is obtained through depressurizing and distilling; purified intermediate II is added to dichloromethane to be reacted with isopentanol at room temperature, triethylamine is taken as alkali, a target coarse product is obtained after a series of treatments of layering, extracting, washing, drying, filtering and the like are conducted on the reactant after reaction, finally fraction of 162-165 DEG C/2 mmHg is collected after depressurizing distillation is conducted to obtain the high-purity phthalic acid n-pentyl isoamyl ester. The purity of the prepared high-purity phthalic acid n-pentyl isoamyl ester can reach up to 99% orabove, and the yield is 60% or above.
Monitoring of phthalic acid monoesters in river water by solid-phase extraction and GC-MS determination
Suzuki,Yaguchi,Suzuki,Suga
, p. 3757 - 3763 (2007/10/03)
An analytical method for monitoring 10 phthalic acid monoesters in river water was investigated by solid-phase extraction, methylation with diazomethane, and GC-MS. Two cartridge-type solid phases packed with octadesyl-coated silica (C18) and styrenedivinyl polymer (PS-2) and one disk-type solid phase made from octadesyl-coated styrene-divinylbenzene polymer (SDB-XD) were investigated in solid-phase extraction. PS-2 gave the highest recoveries of the three solid phases, and recoveries of more than 80% of the monoesters in filtered water samples were obtained at pH 2 to 3 with PS-2 at the spiked level of 0.1 μg L-1, except for monomethyl-phthalate (MMP), in which more than 72% of the monoesters were recovered. For the monoesters in the suspended solids (SS), an acidic methanol extract of SS was added to purified water acidified to pH 2, and the monoesters were extracted with PS-2. The recoveries of the monoesters in SS were more than 80%, but the recoveries of MMP were more than 57%. The method detection limit (MDL) of each phthalic acid monoester in 500 mL of water sample and in 2 mg of dry weight of SS ranged from 0.010 to 0.030 μg L-1 and from 1 to 11 μg g-1 respectively. Monitoring of phthalic acid monoesters in the Tama River in Tokyo was conducted every month from March 1999 to February 2000 using the present method. MMP, mono-n-butyl-phthalate (MBP), and mono-(2-ethylhexyl)-phthalate (MEHP) were detected at concentrations of 0.030-0.0340, 0.010-0.480, and 0.010-1.30 μg L-1. respectively, in the filtered water samples but were not detected in SS. Dimethyl-phthalate (DMP), di-n-butyl-phthalate (DBP), and di-(2-ethylhexyl)-phthalate (DEHP) were detected in the river water at concentrations of 0.010-0.092, 0.008-0.540, and 0.013-3.60 μg L-1, respectively. Diethyl-, di-iso-butyl-, and benzylbutyl-phthalates were also detected at concentrations of nanograms per liter, whereas the corresponding monoesters did not appear. The concentrations of MBP and MEHP in the river water were slightly lower than those of the corresponding diesters at the majority of sampling sites and sampling times.
