Dibromo synthesis

Indole, 3-(dialkylaminomethyl-) alkylation, 4, 275 Indole, 2,3-dibromo-synthesis, 4, 215 Indole, 2,6-dibromo-3-methyl-synthesis, 4, 215 Indole, 1,3-dichloro-synthesis, 4, 214 Indole, dihydrodehydrogenation, 4, 283, 311 in non-silver photography, 1, 383 Indole, 2,3-dihydro-synthesis, 4, 327, 352 Indole, 2,3-dihydroxy-tautomerism, 4, 37, 199 Indole, 4,6-dimethoxy-... 

Isoprene has sometimes been used as a starting matenal in the laboratory synthesis of ter penes In one such synthesis the first step is the electrophilic addition of 2 moles of hydrogen bromide to isoprene to give 1 3 dibromo 3 methylbutane... 

Hydroxybenzaldehyde has extensive use as an intermediate in the synthesis of a variety of agricultural chemicals. Halogenation of Nhydroxybenzaldehyde, followed by conversion to the oxime, and subsequent dehydration results in the formation of 3,5-dihalo-4-hydroxybenzonitrile (2). Both the dibromo- and dhodo-compounds are commercially important contact herbicides, hromoxynil [1689-84-5] (2) where X = Br, and ioxynil [1689-83-4]( where X = I respectively (74). Several hydrazone derivatives have also been shown to be active herbicides (70). 

Polymerization by G—G Goupling. An aromatic carbon—carbon coupling reaction has been employed for the synthesis of rigid rod-like polyimides from imide-containing dibromo compounds and aromatic diboronic acids ia the presence of palladium catalyst, Pd[P(CgH )2]4 (79,80). 

As a variation on the base-catalyzed nucleopbilic displacement chemistry described, polysulfones and other polyarylethers have been prepared by cuprous chloride-catalyzed polycondensation of aromatic dihydroxy compounds with aromatic dibromo compounds. The advantage of this route is that it does not require that the aromatic dibromo compound be activated by an electron-withdrawing group such as the sulfone group. Details of this polymerization method, known as the Ullmaim synthesis, have been described (8). 

Analogous chemistry with 2,3-dibromo-l,4-naphthoquiaone [13243-65-7] (102) has been used ia the synthesis of mitomycin antibiotics for example, (103) [72866-63-8]h.2iS been obtained ia 91% yield (102). 

The first L-folic acid synthesis was based on the concept of a thiee-component, one-pot reaction (7,22). Ttiainino-4(3JT)-pyrirnidinone [1004-45-7] (10) was reacted simultaneously with C -dibromo aldehyde [5221-17-0] (11) and j )-aminoben2oyl-L-glutamic acid [4271-30-1] (12) to yield fohc acid (1). 

Various bromofluoromethanes have been described and proposed for use as fire extinguishing agents (qv). Two that have been recommended highly for this purpose are dibromo difluoromethane [75-61-6] CBr2p2, and bromotrifluoromethane [75-65-8], CBrF, (94). Bromochlorodifluoromethane [353-59-3], CBrClF2, is another fire extinguishing agent. These and similar substituted methanes are potentially useful for the synthesis of other halo—fluoro compounds. 

The first synthesis of 4-isoxazolidinones (540) resulted from the reaction of 2,4-dibromo-2,4-dimethyl-3-pentanone with hydroxylamine (81H(16)1855>. 

Benzo[6]thiophene, 4,7-dialkoxy-synthesis, 4, 930 Benzo[6]thiophene, 2,3-dialkyl-synthesis, 4, 877-878 Benzo[6]thiophene, 3 -(dialkylamino)-synthesis, 4, 925 Benzo[c]thiophene, 1,3-diaryl-oxidative ring opening, 4, 768 Benzo[6]thiophene, 2,3-dibromo-reactions, 4, 830... 

Chroman-4-one, 3-bromo-2-hydroxy-synthesis, 3, 856 Chroman-4-one, 2-/-butyl- H NMR, 3, 583 Chroman-4-one, 3-/-butyl- H NMR, 3, 583 Chroman-4-one, 2,3-dibromo-dehydrobromination, 3, 828 Chroman-4-one, 3,3-dibromo-dehydrobromination, 3, 828 Chroman-4-one, 2,3-dihalogeno-synthesis, 3, 856 Chroman-4-one, 2,2-dimethyl-mass spectra, 3, 617 Chroman-4-one, 2,2-diphenyl-synthesis, 3, 852 Chroman-4-one, 3-hydroxy-synthesis, 3, 856... 

Imidazole, 4,5-dibromo-l-methyl-synthesis, S, 399 Imidazole, 4,5-di-t-butyl-synthesis, S, 483 X-ray diffraction, S, 350 Imidazole, 4,5-dichloro-chlorination, S, 398 synthesis, S, 398, 473 Imidazole, 4-(3,4-dichlorophenyl)-nitration, 5, 433 Imidazole, 4,5-dicyano-hydrolysis, S, 435-436 synthesis, S, 461, 472, 487 Imidazole, 4,5-dicyano-1-vinyl-synthesis, S, 387 Imidazole, 4,5-dihydro-mass spectra, 5, 360 Imidazole, 4-(dihydroxybutyl)-synthesis, S, 484 Imidazole, 4,5-diiodo-nitration, S, 396 synthesis, S, 400 Imidazole, 2,4-diiodo-5-methyl-iodination, S, 400 Imidazole, 1,2-dimethyl-anions... 

Purine, 2,6-dibromo-9- -D-ribofuranosyl-synthesis, 5, 594 Purine, 6,8-di-t-butyl-amination, 5, 542 Purine, 2,6-dichloro-alkylation, 5, 530 reactions... 

Pyran-2-one, 5,6-dibromo-5,6-dihydro-reactions, 3, 735 Pyran-2-one, 5,6-dihydro-allylic bromination, 3, 799 dehydrogenation, 3, 724, 799 H NMR,3, 581 synthesis, 3, 841, 843 Pyran-2-one, 4,6-dimethyl-irradiation, 3, 677 photochemistry, 3, 678 Pyran-2-one, 5,6-dimethyl-chloromethylation, 3, 680 conformation, 3, 631 Pyran-2-one, 5-f ormyl-IR Spectra, 3, 595 Pyran-2-one, 6-formyl-IR spectra, 3, 595 Pyran-2-one, 5-halo-synthesis, 3, 799 Pyran-2-one, 3-hydroxy-IR spectra, 3, 595 Pyran-2-one, 4-hydroxy-methylation, 2, 57 3, 676 pyran-4-one synthesis from, 3, 816 reactions with phosphorus oxychloride, 2, 57 synthesis, 3, 792, 794, 795, 798 tautomerism, 2, 56 3, 642 Pyran-2-one, 4-hydroxy-6-methyl-methylation, 3, 692 reactions... 

X-ray structures, 6, 903 Xanthene, 3,6-bis(dimethylamino)-synthesis, 3, 767 Xanthene, 4-cyano-synthesis, 3, 768 Xanthene, 3,6-dialkylamino-application, 3, 879 Xanthene, 2,7-dibromo-dipole moments, 3, 627 Xanthene, 3,4-dihydro-synthesis, 3, 768... 

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