1201-25-8Relevant articles and documents
A Versatile Synthetic Method of 1-Alkylazulenes and Azulene by the Reactions of 3-Methoxycarbonyl-2H-cycloheptafuran-2-one with in situ Generated Enamines
Yasunami, Masafumi,Miyoshi, Shiro,Kanegae, Noriko,Takase, Kahei
, p. 892 - 899 (1993)
Methyl 3-alkylazulene-1-carboxylates were synthesized in high yields by the reaction of 3-methoxycarbonyl-2H-cycloheptafuran-2-one with in situ generated morpholine enamines of aldehydes.Treatment of the esters with 100percent phosphoric acid gave 1-alkylazulenes in excellent yields.Azulene was also synthesized in a good yield via methyl azulene-1-carboxylate with a modification of this method.
Regioselective and Chemodivergent Synthesis of Azulenolactones and Azulenolactams from Rhodium(III)-Catalyzed Reactions of Azulenecarboxamides with Sulfoxonium Ylides
Lee, Seung Cheol,Son, Jeong-Yu,Kim, Jin Young,Eom, Hyeonsik,Jang, Seong Bin,Lee, Phil Ho
, p. 512 - 524 (2020/11/30)
A regioselective and chemodivergent synthetic approach for azulenolactones and azulenolactams as a new scaffold was demonstrated through Rh(III)-catalyzed reaction of N-methoxyazulene-1-carboxamides with sulfoxonium ylides. Sulfoxonium ylides that act as a precursor of secondary carbene was described, leading to the selective formation of azulenolactones and azulenolactams bearing two substituents on a newly introduced double bond. This method demonstrated functionalization of less reactive 2-position of azulene to overcome the natural reactivity. (Figure presented.).
Carboxylic Acid Directed C-H Arylation of Azulene
Png, Zhuang Mao,Tam, Teck Lip Dexter,Xu, Jianwei
supporting information, p. 5009 - 5013 (2020/07/04)
The first example of directed C-H activation for azulene is reported. A variety of 2-arylazulenes are obtainable exclusively from 1-azulene carboxylic acids, with yields of up to 82percent. Some heteroaryl groups such as pyridine and thiophene are also tolerated in the reaction. The efficacy of the reaction is found to be highly dependent on the conditions, with a phosphate base and a bulky carboxylic acid being key additives.
