4096-72-4Relevant academic research and scientific papers
Synthesis of 2,5- and 2,6-di-t-butyl-4-halo- or -4-methoxy-phenols using silica, lithium perchlorate and lithium bromide as neutral catalysts
Bandgar,Uppalla,Sadavarte
, p. 582 - 583 (2007/10/03)
When a mixture of 4-halo- or 4-methoxy-phenol and excess of t-butyl chloride in the presence of neutral catalyst such as silica or lithium perchlorate or lithium bromide was refluxed, 2,5-and 2,6-di-t-butyl-4-halo or 4-methoxy phenols were obtained in good yields.
Efficient synthesis of 2,5-di-t-butyl-4-fluorophenol
Bandgar,Kasture,Dudhmal, Chaya
, p. 81 - 83 (2007/10/03)
When 4-fluorophenol was refluxed with excess of t-butyl chloride in the presence of various catalysts, e.g. Envirocat EPZG, EPZ10, EPIC, sulfated zirconia, natural kaolinitic clay, zirconium nitrate, zinc chloride and bismuth nitrate, the product obtained was 2,5,di-t-butyl 4-fluorophenol in excellent yield.
Highly Selective Aromatic Chlorinations. Part 2. The Chlorination of Substituted Phenols, Anisoles, Anilines, and Related Compounds with N-Chloroamines in Acidic Solution
Smith, John R. Lindsay,McKeer, Linda C.,Taylor, Jonathan M.
, p. 385 - 392 (2007/10/02)
Phenols, anisoles, anilines, and related compounds are chlorinated in trifluoroacetic acid at room temperature by N-chlorodialkylamines and N-chlorotrialkylammonium salts.With monsubstituted compounds and their 2- and 3-substituted derivatives the reaction occurs efficiently and selectively at the 4-position.The reactivity of these substrates and the selectivity of their chlorinations are determined by electronic rather than steric effects of the substituent.Blocking the reaction with a substituent at the 4-position generally leads to only poor or moderate yields of the 2-chlorinated product.Evidence for radical and cation radical intermediates has been obtained in the reactions of some of the 4-substituted reactants and the mechanism of chlorination is discussed in the light of these findings.The reactions of selected substrates have been scaled up to give laboratory syntheses.
STERICALLY HINDERED 4-HYDROXYBENZENESULFENYL CHLORIDE: REACTIVITY WITH TRIVALENT PHOSPHORUS ESTERS
Pastor, Stephen D.,Spivack, John D.,Steinhuebel, Leander P.,Odorisio, Paul A.
, p. 31 - 34 (2007/10/02)
The reaction of 3,5-di-tert-butyl-4-hydroxybenzenesulfenyl chloride, 1, with the trialkyl phosphites 5a-d gave the corresponding S-(3,5-di-tert-butyl-4-hydroxyphenyl)-O,O-dialkyl phosphorothiolates 6a-d.The formation of 6a-d constitutes chemical evidence for the intermediacy of 1 which was previously inferred from spectroscopic evidence.
Cyclodienones. X. Reaction of Halo-cyclohexadien-1-ones with Phenols in the Presence of α-Picoline and Preparation of 4-Hydroxy- and 2-Hydroxyphenyl Aryl Ethers
Tashiro, Masashi,Itoh, Takashi,Fukata, Gouki
, p. 416 - 420 (2007/10/02)
Reaction of 4-halocyclohexadienones such as 4-bromo-(1a), 4-chloro-2,4,6-tri-t-butyl-(1b), 2,4-dichloro-4,6-di-t-butyl-2,5-cyclohexadien-1-one, and 2,4-dichloro-2,6-di-t-butyl-3,5-cyclohexadien-1-one with phenols in the presence of α-picoline was carried out under various conditions.The reaction of 1a and 1b with phenols afforded the corresponding 2-aryloxy-4,6-di-t-butyl phenols together with various by-products.The AlCl3 catalyzed trans-t-butylation of 2-aroxy-4,6-di-t-butyl-phenols, which were obtained by the above reaction, afforded the corresponding 2-hydroxyphenyl aryl ethers.The similar reaction of 4-aroxy-2,4,6-tri-t-butyl-2,5-cyclohexadien-1-ones also afforded the corresponding 4-hydroxyphenyl aryl ethers.
