Process for preparing dialkylnaphthalene
CA 2241605 C · Owner: Sapre, Ajit Vishwanath · Inventors: Motoyuki, Masahiro; Mcwilliams, John Paul; Sapre, Ajit Vishwanath
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
2,6-Dialkylnaphthalene is prepared from a feedstock comprising naphthalene and an alkylating agent by a process, comprising the steps:, (I) transalkylating isomers of dialkylnaphthalene and naphthalene to produce monoalkylnaphthalene and isomers of dialkylnaphthalene;, (II) separating the product obtained in step (I) into naphthalene, monoalkylnaphthalene, dialkylnaphthalene and other components; (III) alkylating the monoalkylnaphthalene fraction from step (II) with an alkylating agent to produce dialkylnaphthalene; and, (IV) separating 2,6-dialkylnaphthalene from the dialkylnaphthalene fraction in step (II) wherein at least step (I) or step (III) is conducted in the presence of a catalyst …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed June 25, 1998 and granted July 24, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 25, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 25, 2020.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.