16762-20-2Relevant academic research and scientific papers
Light-Induced Mechanistic Divergence in Gold(I) Catalysis: Revisiting the Reactivity of Diazonium Salts
Taschinski, Svenja,D?pp, René,Ackermann, Martin,Rominger, Frank,de Vries, Folkert,Menger, Maximilian F. S. J.,Rudolph, Matthias,Hashmi, A. Stephen K.,Klein, Johannes E. M. N.
supporting information, p. 16988 - 16993 (2019/11/13)
In a systematic study of the Au-catalyzed reaction of o-alkynylphenols with aryldiazonium salts, we find that essentially the same reaction conditions lead to a change in mechanism when a light source is applied. If the reaction is carried out at room temperature using a AuI catalyst, the diazonium salt undergoes electrophilic deauration of a vinyl AuI intermediate and provides access to substituted azobenzofurans. If the reaction mixture is irradiated with blue LED light, C?C bond formation due to N2-extrusion from the diazonium salt is realized selectively, using the same starting materials without the need for an additional photo(redox) catalyst under aerobic conditions. We report a series of experiments demonstrating that the same vinyl AuI intermediate is capable of producing the observed products under photolytic and thermal conditions. The finding that a vinyl AuI complex can directly, without the need for an additional photo(redox) catalyst, result in C?C bond formation under photolytic conditions is contrary to the proposed mechanistic pathways suggested in the literature till date and highlights that the role of oxidation state changes in photoredox catalysis involving Au is thus far only poorly understood and may hold surprises for the future. Computational results indicate that photochemical activation can occur directly from a donor–acceptor complex formed between the vinyl AuI intermediate and the diazonium salt.
A facile one-pot synthesis of 2,3-diarylated benzo[b]furans via relay NHC and palladium catalysis
Jia, Yanyan,Li, Tuanjie,Yu, Chenxia,Jiang, Bo,Yao, Changsheng
, p. 1982 - 1987 (2016/02/18)
An efficient one-pot synthesis of 2,3-diarylated benzo[b]furans was realized through the relay catalysis of N-Heterocyclic Carbene (NHC) and palladium from substituted 2′-bromodiphenylbromomethanes and aryl aldehydes. The easy availability of the starting
Cu-catalyzed intramolecular aryl-etherification reactions of alkoxyl alkynes with diaryliodonium salts via cleavage of a stable C-O bond
Chen, Jing,Chen, Chao,Chen, Junjie,Wang, Guohua,Qu, Hongmei
supporting information, p. 1356 - 1359 (2015/02/05)
A novel Cu-catalyzed intramolecular aryl-etherification reaction of alkoxyl alkynes with diaryliodonium salts is realized. The reactions proceed smoothly to produce valuable oxo-heterocycles with readily available linear starting materials via cleavage of a stable C-O bond. This journal is
One-pot synthesis of 2,3-diarylbenzofurans via sequential iodocyclization and Pd-catalyzed Suzuki coupling reactions of 2-alkynylanisoles with boronic acids in water
Han, Jiang-Sheng,Chen, Su-Qin,Zhong, Ping,Zhang, Xiao-Hong
, p. 3148 - 3155 (2015/10/06)
An efficient approach for the one-pot synthesis of 2,3-diarylbenzofurans via sequential iodocyclization and Pd-catalyzed Suzuki coupling reaction of 2-alkynylanisoles with boronic acids in water is reported. The protocol utilizes water as the solvent and
A high speed parallel synthesis of 1,2-diaryl-1-ethanones via a clean-chemistry C-C bond formation reaction
Veeramaneni, Venugopal Rao,Pal, Manojit,Yeleswarapu, Koteswar Rao
, p. 3283 - 3290 (2007/10/03)
In this report, we describe the parallel as well as conventional synthesis of 1,2-diaryl-1-ethanones via environmentally benign acylation of arenes with in situ generated arylacetyl trifluoroacetates. A wide variety of arylacetic acids I participated in trifluoroacetic anhydride/phosphoric acid mediated C-C bond formation reaction when reacted with arenes of type II to give 1,2-diaryl-1-ethanones III in good to excellent yield. Under the solvent-free conditions these chemical transformations that normally require longer reaction time can be performed within minutes in good yield.
Palladium-catalyzed cross-coupling of benzyl ketones and α,β- unsaturated carbonyl and phenolic compounds with o-dibromobenzenes to produce cyclic products
Terao, Yoshito,Satoh, Tetsuya,Miura, Masahiro,Nomura, Masakatsu
, p. 2345 - 2350 (2007/10/03)
A number of carbonyl and phenolic compounds efficiently couple with o- dibromobenzenes in the presence of a palladium catalyst and a base to give the corresponding oxygen-containing heterocycles or carbocyclic compounds. Thus, from the reactions of benzyl phenyl ketones, 1-naphthols, and α,β- unsaturated aldehydes and ketones, benzofuran, benzopyran, benzocyclobutane, and indene derivatives, respectively, are produced selectively via the successive formation of C-C and C-O bonds or of two C-C bonds.
Cyclodeshydratation d'aryloxy-2 diaryl-1,2 ethanones en diaryl-2,3 benzofurannes. Influence de la substitution sur la competition entre deux chemins reactionnels
Montfort, Bernard,Laude, Bernard,Vebrel, Joel,Cerutti, Ernest
, p. 848 - 854 (2007/10/02)
Many of the methods for synthesizing derivatives of 2,3-diaryl benzofurans imply cyclodehydration of 1,2-diaryl 2-aryloxyethanones, leading often to a mixture of two isomers which differ by the presence of the aryl substituent at positions C-2 or C-3 of benzofuran.This isomerisation is explained by a competition between two possible mechanisms.Either a direct electrophilic substitution or the intermediate formation of an α-acylcarbenium ion.This study deals with the competition as determined by the substitution of aryl groups in the initial substrate.Each 2,3-diarylbenzofuran was synthesized previously using an unambiguous method.
