Bromomethanesulfonyl bromide

Block and Aslam441 reported a novel variant of the Ramberg-Backlund reaction in which a,/J-unsaturated a -bromoalkyl sulfones 368 afforded 1,3-dienes upon treatment with base. Since a -bromoalkyl sulfones 368 can be obtained readily by the initial treatment of olefins with bromomethanesulfonyl bromide under photoirradiation and subsequent treatment with triethylamine, this reaction was utilized for preparation of dienes which contain one additional carbon over that of the corresponding olefin. Starting from the cyclic olefins 369-372 the 1,3-dienes 373-376 were obtained442. 

B romo-3,4-di methoxybenzaldehyde eye1ohexy1i mi ne Cyelohexanami ne, N-[(2-brofflo-4,b-dimethoxyphenyl)methylene]- (73252-55-8), 65, 108 BROMOMETHANESULFONYL BROMIDE METHANESULFONYL BROMIDE, BROMO- ... 

A GENERAL SYNTHETIC METHOD FOR THE PREPARATION OF CONJUGATED DIENES FROM OLEFINS USING BROMOMETHANESULFONYL BROMIDE 1,2-DIMETHYLENECYCLOHEXANE (Cyclohexane, 1,2-bis(methylene)-)... 

On occasion bromomethanesulfonyl bromide undergoes spontaneous, exothermic addition to olefins. While this problem was not encountered with 1-methylcyclohexene, it is desirable to mix the reagents at low temperature to avoid a possible vigorous spontaneous reaction and to maximize the yield of adduct. 

Bromomethanesulfonyl bromide, BiCH,S02Br (1). The reagent is a pale yellow liquid that is stable for several weeks at 25°. It is prepared by reaction of Br, with an aqueous slurry of 1,3,5-trithiane (46% yield). 

Bicyclic dienes have been sulfobrominated. Norbornadiene reacts with bromomethanesulfonyl bromide to give a 1 1 mixture of an c/n/r -adduct ( Wo-6-bromo-c.vo-5-norbornen-2-yl bro-momethyl sulfone) and 5-bromo-3-nortricycyl bromomethyl sulfone ([Pg.1184]

Other examples of the preparation of dienes from olefins using bromomethanesulfonyl bromide (82) are shown in equations 49-5249. 

Block and Aslam98 have reported sulfene formation as in reaction 14. It proceeds readily at room temperature in two hours, and has certain advantages in comparison with the reaction of methanesulfonyl chloride with triethylamine. These include formation of the sulfene adduct with cyclopentadiene, bromomethanesulfonyl bromide with bromine,... 

The overall process involving addition of a-bromomethanesulfonyl bromide to olefins and subsequent dehydrobromination followed by base-promoted viny-logous Ramberg-Backlund reaction constitutes a three-step transformation of olefins into 1,3-dienes (Scheme 14) [107]. Conjugated dienes are also available from the Ru(II)-catalyzed reaction of alkenesulfonyl chlorides with olefins [108],... 

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