146256-23-7Relevant academic research and scientific papers
Naphthalene-catalysed lithiation of functionalized chloroarenes: Regioselective preparation and reactivity of functionalized lithioarenes
Guijarro, Albert,Ramon, Diego J.,Yus, Miguel
, p. 469 - 482 (1993)
The lithiation of different functionalized chloroarenes (dichlorobenzenes 1 and 3, mono and dichlorophenols 9 and 14, and chloropivalanilides 18) in the presence of a catalytic amount of naphthalene leads to the corresponding functionalized lithioarenes, which react with electrophiles to give the expected polyfunctionalized aromatic molecules 2, 4, 10, 19, 21, 22 and 24 in a regioselective manner. In the case of starting from chlorinated phenols or anilides a deprotonation of the functional group is carried out prior to the lithiation process; only for 2-chloropivalanilide 18o a coupling reaction leading to 2-n-butylpivalanilide is observed when an excess of n-butyllithium is used in the deprotonation step.
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
