73509-12-3Relevant academic research and scientific papers
Rhodium-Catalyzed Annulations of 1,3-Dienes and Salicylaldehydes/2-Hydroxybenzyl Alcohols Promoted by 2-Ethylacrolein
Li, Hong-Shuang,Xiong, Yang,Zhang, Guozhu
supporting information, p. 4246 - 4251 (2018/10/02)
A rhodium-catalyzed 2-ethylacrolein-promoted protocol enables the annulation reactions of 1,3-dienes with either salicylaldehydes or 2-hydroxybenzyl alcohols leading to 2-alkylchroman-4-ones with high regioselectivity. This research highlights the use of 2-ethylacrolein which probably serves as a tool of bidentate coordination to rhodium intermediates. Mechanistic studies reveal that the transformation proceeds through the 1,4-hydroacylation pathway to access unsaturated linear ketones with subsequent oxo-Michael addition. (Figure presented.).
An Efficient Synthesis of 6-oxa-spiro[3.4]octan-1-one Derivates Through 3-diazochroman-4-one and Alkene
Xiao, Meiling,Zhang, Fuming,Du, Zhe,Ma, Baochun
supporting information, p. 911 - 916 (2018/01/22)
Spiro[2,2-dimethyl-benzofuran,bicyclo [4.2.0]octane]-7′-one with fused and spirocyclic oxygen-containing rigid skeleton structure is obtained via Wolff rearrangement and cycloaddition with good yields. Then Spiro[2,2-dimethyl-benzofuran,hexahydro-isobenzofuran]-7′-one is synthesized by further Baeyer-Villiger oxidation. These two kinds of products have a special fused and spirocyclic oxygen-containing rigid skeleton structure and are reported by our group. (Figure presented.).
Synthesis of new chromeno[4,3-b]pyrazolo[4,3-e]pyridines derivatives with antimicrobial evaluation
El-Essawy, Farag A.,El-Etrawy, Abd-Allah. Sh.
, p. 191 - 195 (2014/02/14)
A series of 2-oxo-2,5-dihydro-1H-chromeno[4,3-b]pyridine derivatives were obtained by using a one-pot three component reaction of 2,2-disubstituted chroman-4-one with aromatic aldehydes and 2-cyanoacetamide in the presence of sodium hydroxide under solvent-free conditions. Heating chromenopyridine derivatives with phosphoryl chloride gave the corresponding chloro derivatives. The reaction of the chloro derivatives with hydrazine hydrate afforded dihydrochromeno[4,3-b]pyrazolo[4,3-e]pyridines derivatives. Condensation of the dimethyl derivative compound with the aromatic aldehydes gave 8-Arylideneamino-6,6-dimethyl-10H-chromeno[4,3-b]pyrazolo[4,3-e]pyridine.
Synthesis and biological screening of novel thiadiazoles, selenadiazoles, and spirocyclic benzopyran by ultrasonic and microwave irradiation
Shinde,Sonar,Shingate,Shingare
experimental part, p. 1594 - 1603 (2010/10/01)
We describe the synthesis of novel thiadiazole, selenadiazole, and spirocyclic benzopyrans via the semicarbazides 3 and thiosemicarbazides 3 of 2-ethyl-2-methyl-4H-chromen-4-ones 1 by conventional and nonconventional methods. The microwave and ultrasonic irradiation methods form the respective products in excellent yields in very short reaction time as compared to the conventional method. The synthesized compounds were tested for antimicrobial screening against bacteria and fungi show moderate activity. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. Copyright Taylor & Francis Group, LLC.
Cycloadditions with 2,2-dialkyl-3-thioxochroman-4-one S-sulfides including an unprecedented [3 + 5] cycloaddition
El-Essawy, Farag A. G.,Yassin, Salah M.,El-Sakka, Ibrahim A.,Khattab, Ahmed F.,Sotofte, Inger,Madsen, Jorgen gaard,Senning, Alexander
, p. 9840 - 9845 (2007/10/03)
We report the facile generation of the chroman-4-one-derived thiosulfines 10 under mild conditions by our well-established nucleophilic 'unzipping' of the corresponding acetyl α-chloroalkyl disulfides 9 which in turn can be prepared from the corresponding α-chloro sulfenyl chlorides 8. Spontaneous partial loss of sulfur from 10, most probably by the disproportionation of 10 to 11 and 12, generates the expectedly reactive β- oxo thioketones 11 which partly dimerize in a precedented Diels-Alder fashion, to give the 1,3,4-oxadithiins 13, and partly cycloadd to 10 to form the 1,2,4-trithiolanes 14 in a well-precedented fashion. Dimerization of 10 can occur in two competing ways: the precedented nonconcerted [3 + 3] cycloaddition (to give 1,2,4,5-tetrathianes 15) and the unprecedented concerted [3 + 5] addition to give 1,3,4,5,6-oxatetrathiocins 16. In the latter interaction one molecule of 10 behaves as a 1,5-dipole and a second molecule as a 1,3-dipole. In one case (10d) extensive sulfur scrambling takes place with formation of the 1,2,3,4,5,6-hexathiepane 17d. It is remarkable how sensitive the reactions of 10 are to minor variations of the simple alkyl substituents in the 2-position. In addition to the usual spectroscopic characterization all isolated key compounds were subjected to X-ray single- crystal structure determinations.
Thallium(III) p-tosylate mediated oxidative rearrangement in substituted chromanones: A novel approach to the synthesis of substituted chromones and tetrahydroxanthones
Singh, Om V.,George, Varughese,Kapil, Randhir S.
, p. 856 - 864 (2007/10/03)
On treatment with thallium(III) p-tosylate, subtituted chromanones undergo smooth dehydrogenation to afford substituted chromones while 2,2-dialkylchromanones undergo oxidative 2,3-alkyl migration to yield 2,3-dialkylchromones in high yields.The migratory aptitude of different alkyl groups with respect to methyl group has also been studied. 2-Spirochromanones undergo oxidative 2,3-alkyl migration to afford tetrahydroxanthones which on dehydrogenation with DDQ afford xanthones in good yields.
A New Reaction of α-Chloro-α-chlorosulfenyl Ketones: Facile Syntheses of 3,3-Dichloro- and 3-Chloro-Chroman-4-ones and Thiochroman-4-ones
Gabbutt, Christopher D.,Hepworth, John D.,Heron, B. Mark
, p. 5245 - 5254 (2007/10/02)
3-Chloro-3-chlorosulfenylchroman-4-ones are efficiently obtained from chroman-4-ones by treatment with thionyl chloride.Direct oxidation affords 3,3-dichlorochroman-4-ones, whilst conversion to the sulfenamides prior to oxidation provides a facile route to 3-chlorochroman-4-ones.
