3-Substituted Thiophenes. I

Synthesis of benzo[1,2‐b′:4,5‐b′]dithiophene and its 4,8‐Dimethoxy and 4,8‐dimethyl derivatives

“…CON(CHd2 &Ityl-Li & 1 . )Zn /NaOH 2,)Methyl p-- ' ' ' ' 2 0 toluenesulfonat e 0 OCH, S 5 6 7 4,&Dimetbylbenzo[l,Z: 4,5b']dithiophene (13) method described by Rao The structures of the compounds described in this paper were confirmed by elemental analysis and spectroscopic methods. The 'H NMR spectra show typical doublets of the AB spin system of the condensed thiophene rings with coupling constants of about 5 to 5.5 Hz.…”

Efficient and Convenient Oxidation of Organic Halides to Aldehydes and Ketones Catalyzed by H5IO6/V2O5 in Ionic Liquid [bmpy][PF6]

“…In conclusion, we have demonstrated an efficient and selective oxidation of organic halides to aldehydes and ketones by using H 5 IO 6 /V 2 O 5 catalyst system in the ionic liquid [bmpy]PF 6 . Most importantly, the catalysts are very easy to handle and can be recycled and reused without any significant loss of catalytic activity.…”

“…1 Up to now, many publications in the open literature have been found in synthesis of these type of compounds, and a well known method for such a synthesis constitutes the oxidation of benzyl halides. 2,3 Hass-Bender reaction 4,5 and Sommelet reaction 6 are two classic methods for such a conversion. While each has some limitations, the former method is only satisfied for para-substituted substrates, the latter unfortunately has limited substrate scope.…”

Effects of Base for the Efficient Synthesis of 4-Formylcoumarins and 4-Formylcarbostyrils

“…Gattermann reaction using hydrogen cyanide, [2] formylation of phenols or amines, [3] with hexamine (Duff reaction) in presence of boric acid, hexamine and glycerol mixture at high temperature results low yield, hydroformylation, [4] of unsaturated compounds using cobalt catalyst, Sommalet, [5] formylation of halo methyl compounds in presence of hexamine, ortho and para-formylation of phenols via Reimer-Teimann reaction, [6] aromatic methyl halides interaction with sodium 2-propenenitrate, [7] decomposition of arylosulphonohydrazides, [8] followed by base treatment at elevated temperature but the method fails in case of aliphatic sulphonohydrazides. Controlled oxidation of side chain, [9] and primary alcohols, [10] leads to aromatic aldehydes.…”