78131-81-4Relevant academic research and scientific papers
A Simple Synthesis of Densely Substituted Benzofurans by Domino Reaction of 2-Hydroxybenzyl Alcohols with 2-Substituted Furans
Abaev, Vladimir T.,Chalikidi, Petrakis N.,Kekhvaeva, Anna E.,Makarov, Anton S.,Trushkov, Igor V.,Uchuskin, Maxim G.
, p. 3747 - 3757 (2019/09/30)
The Br?nsted acid-catalyzed cascade synthesis of densely substituted benzofurans from easily available salicyl alcohols and biomass-derived furans has been developed. The disclosed sequence includes the intermediate formation of 2-(2-hydroxybenzyl)furans
Low-energy collision-induced fragmentation of negative ions derived from ortho-, meta-, and para-hydroxyphenyl carbaldehydes, ketones, and related compounds
Attygalle, Athula B.,Ruzicka, Josef,Varughese, Deepu,Bialecki, Jason B.,Jafri, Sayed
, p. 1207 - 1217 (2008/03/11)
Collision-induced dissociation (CID) mass spectra of anions derived from several hydroxyphenyl carbaldehydes and ketones were recorded and mechanistically rationalized. For example, the spectrum of m/z 121 ion of deprotonated ortho-hydroxybenzaldehyde shows an intense peak at m/z 93 for a loss of carbon monoxide attributable to an ortho-effect mediated by a charge-directed heterolytic fragmentation mechanism. In contrast, the m/z 121 ion derived from meta and para isomers undergoes a charge-remote homolytic cleavage to eliminate an ?H and form a distonic anion radical, which eventually loses CO to produce a peak at m/z 92. In fact, for the para isomer, this two-step homolytic mechanism is the most dominant fragmentation pathway. The spectrum of the meta isomer on the other hand, shows two predominant peaks at m/z 92 and 93 representing both homolytic and heterolytic fragmentations, respectively. 18O-isotope-labeling studies confirmed that the oxygen in the CO molecule that is eliminated from the anion of meta-hydroxybenzaldehyde originates from either the aldehydic or the phenolic group. In contrast, anions of ortho-hydroxybenzaldehyde and 2-hydroxy-1-naphthaldehyde, both of which show two consecutive CO eliminations, specifically lose the carbonyl oxygen first, followed by that of the phenolic group. Anions from 2-hydroxyphenyl alkyl ketones lose a ketene by a hydrogen transfer predominantly from the α position. Interestingly, a very significant charge-remote 1,4-elimination of a H2 molecule was observed from the anion derived from 2,4-dihydroxybenzaldehyde. For this mechanism to operate, a labile hydrogen atom should be available on the hydroxyl group adjacent to the carbaldehyde functionality. Copyright
Alkylation of substituted benzaldehyde on a solid matrix by using Grignard reagent
Patel, Sabita,Panda, Mamata P.,Kuanar, Minati,Mishra
, p. 1299 - 1301 (2007/10/03)
Phase transfer alkylation of aromatic aldehydes has been attempted on silica matrix in ether medium. The alkylation of substituted benzaldehyde by using Grignard reagent from isopropyl bromide yields substituted benzyl alcohols in good yield. Products fro
Photochemical Reactions of o-Alkenylphenols and 1-Alkenyl-2-naphthol with Alkylamines: Amination via Photoinduced Proton Transfer
Yasuda, Masahide,Sone, Tatsuya,Tanabe, Kimiko,Shima, Kensuke
, p. 459 - 464 (2007/10/02)
Irradiation of o-alkenylphenols 1a-c and 2a-e in the presence of alkylamines gave o-(1-alkylaminoalkyl)phenols 4a-n and 5a-e in relatively good yields.Deprotonation of these o-alkenylphenols by the amines occurs in the excited singlet state to give the excited singlet state of the phenolate anion 7 and the ammonium ion.The proton transfer from the ammonium ion to the alkenyl group of 7 generates the zwitterion 8 that allows the nucleophilic addition of the amine at the benzylic cation centre.Similar photoamination of 1-(2-methylpropenyl)-2-naphthol 3 with alkylamines occured to give 1-(1-alkylamino-2-methylpropyl)-2-naphthols 6a-b.
Amination of o-Alkenylphenols with Alkylamines via Photoinduced Proton Transfer
Yasuda, Masahide,Sone, Tatsuya,Tanabe, Kimiko,Shima, Kensuke
, p. 453 - 456 (2007/10/02)
Irradiation of o-alkenylphenols with alkylamines resulted in Markovnikov-type amination to give o-(1-alkylaminoalkyl)phenols in relatively good yields. The photoamination was initiated by a proton transfer from the ammonium ion to the alkenyl group of o-alkenylphenolate anion in the excited state in the ion pair formed between the phenols and the amines. The resulting zwitter ion allowed the nucleophilic addition of the amine at the benzylic cation center.
