- Synthesis method of high-purity phloroglucinol compound
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The invention discloses a one-step chemical catalytic synthesis method of high-purity phloroglucinol by taking 3,5-dichlorophenol as a starting material and taking strong base and a catalyst as auxiliary materials. Through the method, the phloroglucinol compound with high molar yield, high purity and low cost can be effectively synthesized.
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Paragraph 0019
(2021/06/09)
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- METHOD FOR THE SYNTHESIS OF INITIATORS FOR TELECHELIC POLYISOBUTYLENES
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A new methodology for the synthesis of a novel difunctional- and a known trifunctional initiator, i.e., 1,3-di(2-methoxy-2-propyl)-5-isopropyl benzene and 1,3,5-tri(2-methoxy-2-propyl) benzene, respectively, for the preparation of di- and tri-telechelic polyisobutylenes. The synthesis proceeds in three steps: 1) catalytic peroxidation of 1,3,5-triisopropylbenzene, 2) reduction of the peroxides to the corresponding alcohols, and 3) methylation of the alcohols. By controlling the conversion of the key peroxidation step the relative ratio of di- and tri-fiinctional intermediates can be controlled. By the use of the 1,3-di(2-methoxy-2-propyl)-5-isopropyl-benzene, well-defined di-methoxy telechelic polyisobutylenes can be synthesized. Although the overall combined yield of the two initiators was only 14-20%, because of the low cost of the starting material, reagents used, and simple manipulations these compounds represent the most cost effective initiators to-date for the preparation of telechelic polyisobutylenes.
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Page/Page column 14-15
(2012/07/27)
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- Aerobic oxidation of 1,3,5-triisopropylbenzene using N-hydroxyphthalimide (NHPI) as key catalyst
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The first systematic study on the aerobic oxidation of 1,3,5- triisopropylbenzene was examined by the use of N-hydroxyphthalimide (NHPI) as a key catalyst. It was found that 1,3,5-triisopropylbenzene was efficiently oxidized with O2 in the presence of a catalytic amount of NHPI and azobisisobutyronitrile (AIBN) at 75°C. Upon treatment of the resulting products with sulfuric acid followed by acetic anhydride led to 5-acetoxy-1,3-diisopropylbenzene and 3,5-diacetoxy-1-isopropylbenzene as major products and a small amount of 1,3,5-triacetoxybenzene. When t-butylperoxypivalate (BPP) was employed as a radical initiator, the oxidation could be achieved in good yield even at 50°C. This oxidation provides a facile method for preparing phenol derivatives bearing an isopropyl moiety, which can be used as pharmaceutical starting materials.
- Aoki, Yasuhiro,Hirai, Naruhisa,Sakaguchi, Satoshi,Ishii, Yasutaka
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p. 10995 - 10999
(2007/10/03)
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