69888-42-2Relevant academic research and scientific papers
Molecular iodine catalyst promoted synthesis of chromans and 4-aryl-3,4-dihydrobenzopyran-2-ones via [3+3] cyclocoupling
Naik, Mayuri M.,Kamat, Durga P.,Tilve, Santosh G.,Kamat, Vijayendra P.
, p. 5221 - 5233 (2014/07/08)
Molecular iodine as an inexpensive catalyst is described in the construction of 2-substituted or 2,2-disubstituted chromans and 4-aryl-3,4-dihydrobenzopyran-2-ones via [3+3] cyclocoupling. For the synthesis of chromans, phenols and allylic alcohols were refluxed in chloroform in presence of 20 mol % I2 while [3+3] cyclocoupling of phenols and cinnamic acids proceeded to give 4-aryl-3,4-dihydrobenzopyran-2-ones using 30 mol % I2. Later reaction occurs via a tandem hydroarylation- esterification process at 120-130°C under solvent free conditions. Chromans were obtained in 20-92% yields and substituted 4-aryl-3,4-dihydrobenzopyran-2- ones were obtained in 5-85% yields.
Molecular iodine catalyst promoted synthesis of chromans and 4-aryl-3,4-dihydrobenzopyran-2-ones via [3+3] cyclocoupling
Naik, Mayuri M.,Kamat, Durga P.,Tilve, Santosh G.,Kamat, Vijayendra P.
, p. 5221 - 5233 (2014/12/10)
Molecular iodine as an inexpensive catalyst is described in the construction of 2-substituted or 2,2-disubstituted chromans and 4-aryl-3,4-dihydrobenzopyran-2-ones via [3+3] cyclocoupling. For the synthesis of chromans, phenols and allylic alcohols were refluxed in chloroform in presence of 20 mol % I2while [3+3] cyclocoupling of phenols and cinnamic acids proceeded to give 4-aryl-3,4-dihydrobenzopyran-2-ones using 30 mol % I2. Later reaction occurs via a tandem hydroarylation-esterification process at 120-130 °C under solvent free conditions. Chromans were obtained in 20-92% yields and substituted 4-aryl-3,4-dihydrobenzopyran-2-ones were obtained in 5-85% yields.
Nucleophilic attack of intramolecular hydroxyl groups on electron-rich aromatics using hypervalent iodine(III) oxidation
Hata, Kayoko,Hamamoto, Hiromi,Shiozaki, Yukiko,C?mmerer, Simon B.,Kita, Yasuyuki
, p. 4052 - 4060 (2007/10/03)
The hypervalent iodine(III) reagent, phenyliodine bis(trifluoroacetate) (PIFA)-mediated oxidative nucleophilic substitution of electron-rich aromatics involving aromatic cation radical intermediates was utilized in the direct aromatic carbon-oxygen bond f
Montmorillonite clays in organic synthesis: A one-pot conversion of phenols to 2,2-dimethylbenzopyrans
Dintzner, Matthew R.,McClelland, Kristen M.,Morse, Kara M.,Akroush, Michael H.
, p. 2028 - 2030 (2007/10/03)
2,2-Dimethylbenzopyran derivatives were generated through a one-pot Montmorillonite K10 clay-catalyzed condensation of substituted phenols with prenyl bromide.
A novel and direct synthesis of chroman derivatives using a hypervalent iodine(III) reagent
Hamamoto, Hiromi,Hata, Kayoko,Nambu, Hisanori,Shiozaki, Yukiko,Tohma, Hirofumi,Kita, Yasuyuki
, p. 2293 - 2295 (2007/10/03)
The direct aromatic carbon-oxygen bond-formation reaction was described and the novel and simple synthetic method for chroman derivatives involving aromatic cation radical intermediates was developed using the hypervalent iodine(III) reagent, phenyliodine(III) bis(trifluoroacetate) (PIFA).
Aromatic ring synthesis by 1,3-Michael-Claisen annulation: Application to a Trolox analogue and to Precocene II
Solladie,Boeffel,Maignan
, p. 2065 - 2074 (2007/10/03)
A Trolox analogue, 3,4-dihydro-2-ethoxycarbonyl-6-methoxy-7-hydroxybenzopyran and Precocene II, were prepared from substituted α-methylene-δ-valerolactone and 1,1-bis-(methylthio)-2-propanone or butanone, via a 1,3-Michael-Claisen annulation.
CHROMENES AND CHROMANONES. PART II. THE BIRCH REDUCTION OF PRECOCENE I AND PRECOCENE II
Aniol, Miroslaw,Wawrzenczyk, Czeslaw
, p. 2655 - 2662 (2007/10/02)
The reduction of precocene I (1a), precocene II (1c) and 6-methoxy-2,2-dimethyl-2H-chromene (1b) with sodium or lithium in liquid ammonia was examined.The phenolic compounds and the bicyclic one with partialy reduced benzene ring were obtained as the majo
