P Bromobenzoyl chloride

BrC CO-SCSN, mw 302.19, N 13.91% col rhmb plates, mp 99 101°(dec) very sol in CHClj, moderately sol in CSa or CC14 and si sol in acet, EtOAc, ale, MeOH, eth or benz. This compd was pptd, together with NaCl, by the interaction of p-bromobenzoyl chloride and Na azidodithiocarbonate in acet. The prod was purified by crystn from chlf... 

The four related compounds oxalomycin (157), neooxalomycin (158), cur-romycin A (159), and curromycin B (160) were reported in 1985 157 and 158 were isolated from a yet to be identified Streptomyces species (79, 80) and 159 and 160 from an ethidium bromide-treated strain of S. hygroscopicus (81, 82). The absolute configuration of oxalomycin (157) and neooxalomycin (158) has been determined by application of a combination of X-ray crystallography and chemical correlation to degradation products, the important derivatives being the p-bromobenzoate 161, obtained from 157 by ozonolysis-reduction, acetylation, partial hydrolysis, and reacylation with p-bromobenzoyl chloride, and the erythro acetate 162 which was obtained along with the threo compound 163 after acetylation of the ozonolysis products of 157 (79, 80). No stereochemical infor-... 

A solution of 8.5 g. (0.04 mole) of p-bromobenzoyl chloride (p. 41) in 10 ml. of benzene is added slowly with vigorous stirring to a mixture of 5 g. of sodium j)eroxide and 50 ml. of ice-cold water. The precipitated white solid is removed by filtration and recrystallized from methanol to give 5.5 g. (71%) of p-bromobenzoyl peroxide, m.p. 143.5 dec. 

The absolute configuration of caryose was determined applying the Exciton Chiral Coupling to 36 [Fig. (8)], which is the di-O-p-bromobenzoyl derivative, obtained as the main product of the isopropylidenation of the monosaccharide equilibrium mixture (34a, 34b and 35) followed by esterification with p-bromobenzoyl chloride. The results obtained have suggested for caryose the absolute configuration... 

We had previously sought to determine the configuration of C9 through X-ray analysis but stmggled to obtain crystals of sufficient quality despite several attempts with different intermediates. In the end, we decided to use the previously described Curtius rearrangement sequence with p-bromobenzoyl chloride in place of the fumaroyl chloride. Gratifyingly, amide 68 did provide crystals suitable for X-ray analysis (Figure 5). 

The hydrazone resin (0.5 g, 0.45 mmol) was dried in high vacuum overnight and suspended in 5 mL pyridine. To this suspension was added 1.35 mmol p-bromobenzoyl chloride (3 eq.) under argon. The mixture was shaken at 80°C overnight. After cooling, the resin was filtered and washed three times with DMF, DMF/H2O (v/v = 90/10), DMF, dichloromethane, ethyl acetate, and methanol. 

Unlike aryl chlorides, acyl chlorides are quite reactive, although not often used. Oxidative addition of palladium(O) to the acid chloride 5.44 generates an acyl palladium(II) complex 5.46 (Scheme 5.12). This may undergo decarbonylation or not prior to alkene insertion depending on the reaction conditions, and the substrate structure (Schemes 5.13 and 5.14). Acid chlorides are more reactive than aryl bromides and selective coupling at the two positions of p-bromobenzoyl chloride 5.53 with different alkenes is possible (Scheme 5.15). ... 

Preparation by reaction of p-bromobenzoyl chloride with phenol in the presence of alu-mininm chloride [165],... 

Preparation by demethylation of 4-bromo-4 -methoxybenzophenone (SM) with aluminium chloride in refluxing benzene for 8 h. SM was obtained by Friedel-Crafts acylation of anisole with p-bromobenzoyl chloride [917],... 

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