Thiophene diol, reaction with

Hybrid linear tri- and tetra-oligomers possessing combinations of furan, thiophene or pyrrole have been obtained (2000TL2919, 2001T7323) by BFs-catalysed reactions of diols 18, and 22 with pyrrole, etc. The diols are obtained from reactions of bisanions of the parent heterocycles or their dimers with ketones. 

The Wittig reaction of the quinone (675) with ylide generated from (676) gives the benzo[c]-thiophene (677) in moderate yield (Equation (121)) <86JCS(P1)4I5>. Conversion of the diol (678) to the benzo[c]thiophene (679) was also reported <85MI 2ll-0i>. 

The reactions of sulfur with dimethylformamide dimethylacetal (96JPR403) and 2,5-dimethylhex-3-yne-2,5-diol (94H143) give substituted thieno[3,2-i>]thiophenes. 

The question of guest exchange in inclusion compounds received little attention, despite that fact that such processes are important for sensing and catalysis based on inclusion. However, a number of host-guest systems with organic and metal-containing hosts that entrap volatile guests were recently studied.The host l,l,6,6-tetraphenyl-2,4-diyne-1.6-diol H) forms inclusion compounds with tetrahydrofuran (THF), and thiophene (THIO), and we analyzed the dynamics of the reaction ... 

This route can be used to prepare thiophenes with adjacent bulky groups 3,4-di-ferf-butylthiophene [102] and 3,4-di(adamant-l-yl)thiophene [103] can be accessed. Another nice example (Scheme 64) is the reaction of 1,3-dichloropropanone with hydrogen sulfide, which produces diketone 40. The application of the pinacol-forming conditions gives rise to the diol 41 and double dehydration produces the bicyclic l//,3//-thieno[3,4-c]thiophene 42 [104],... 

Highly substituted tetrahydrothiophens can also be prepared by two related routes, the first of which involves the Michael addition of mercapto-esters to benzylidene-benzoylacetonitriles in the presence of triethylamine/ The authors had expected the formation of a 3-oxotetrahydrothiophen by a Dieck-mann-type cyclization. In the second reaction the base-catalysed condensation of diketosulphides with 1,2-diketones led smoothly to tetrahydrothiophen diols rather than the expected thiophens." In both cases the products are probably resistant to dehydration due to steric crowding. 

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