3-Bromo-1,1 -dichlorobenzo

The sulfones of 3-methyl-, 3-methoxy-, 3-dimethylamino-, and 3-piperidinobenzo[6]thiophene yield only sulfur dioxide and intractable tars on being heated in inert solvents, whereas 2-bromo- and 2,3-dichlorobenzo[6]thiophene-l,1-dioxide are extremely stable to... 

C7H4BrF02 2-bromo-4-fluorobenzoic acid 1006-41-3 25.00 1.7218 2 9747 C7H4CI202 2,6-dichlorobenzoic acid 50-30-6 25.00 1.4487 2... 

C7H4BrClN20 2-amino-5-bromo-6-chloroben20xa20le 64037-09-8 560.65 49 741 1.2 9745 C7H4CI202 2,4-dichlorobenzoic acid 50-84-0 574.15 51.052 2... 

C7H4BrCIN20 2-amino-6-bromo-5-chloroben20xa20le 64037-08-7 560.65 49.741 2 9746 C7H4CI202 2,5-dichlorobenzoic acid 50-79-3 574.15 51.052 1.2... 

The analogue norbornane compoimd 165 was obtained from bromo isothiazolone dioxide 163 and qrdopentadiene, which gave the intermediate cycloadduct (95%), which was transformed into derivative 164 (40% overall yield) by reduction of the double bond followed by elimination of hydrogen bromide and deprotection (48%). The latter was converted to the target dichlorobenzoate 165 as described before for compounds 162 (Scheme 43) [53]. 

Van den Tweel, W.J.J., J.B. Kok, and J.A.M. de Bont. 1987. Reductive dechlorination of 2,4-dichlorobenzoate to 4-chlorobenzoate and hydrolytic dehalogenation of 4-chloro, 4-bromo-, and 4-iodobenzoate by Alcaligenes denitrificans NTB-1. Appl. Environ. Microbiol. 53 810-815. 

Reactions of 2,3-dichlorobenzo [b] thiophene 1,1-dioxide 123 with nitrogen and oxygen nucleophiles produce substitution products, 124 and 125, at the 3-position because the addition of nucleophiles takes place exclusively at that position (Scheme 70) [196-198]. However, in the case of 2-bromo-3-phenylben-zo [ b] thiophene 1,1 -dioxide 126, nitrogen nucleophiles added to carbon 2 to give compounds 127 (Scheme 71) [194]. 

Nucleophilic substitution in 2,3-dichlorobenzo[b] thiophene 1,1-dioxides takes place preferentially in the 3-position.352 2-Bromobenzo[i>]thiophene 1,1-dioxide is converted into the 3-bromo isomer by KNH2-NH3215 it is well established that a 2-bromine atom is replaced by a nucleophile with rearrangement to give the 3-substituted product.1 A 3-chloro substituent, activated by an adjacent ester or ketone function, is very readily replaced, and cyclization can often take place to form an additional heterocyclic... 

The synthesis of 3-bromo-l,l-dichlorobenzo[i ]selenophene-2-carbox-ylic acid is shown below. 

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