Pyridinium Bromide Perbromide Synthesis Essay

Abstract

(selective brominating reagent for ketones,2 acetals,3 alkenes,4 activated phenols,5 anilines,6 and nitrogen heterocycles;7 mild oxidation/dehydrogenation reagent8)

Alternate Names: PHBP; pyridinium bromide perbromide; pyridinium perbromide; pyridinium tribromide.

Physical Data: mp 101–103 °C (39.7% Br), mp 132–134 °C (47% Br),7 135 °C (50% Br).9

Solubility: sol acetic acid, methanol, ethanol, n-butanol, THF, ether (wet); insol water, carbon tetrachloride, ethyl bromide, ether (anhydrous), benzene, toluene, ligroin, petroleum ether.9

Form Supplied in: red-orange solid, generally 90–97% pure; commercially available.

Analysis of Reagent Purity: iodometric titration.10

Preparative Method: from pyridine, 48% hydrobromic acid, and bromine.1, 7 The bromine content varies depending on the method of preparation.7, 11

Purification: recrystallization from ethanol.12 Recrystallization from acetic acid reduces the bromine content. Pure material can be obtained by adding bromine to impure material until a paste is produced. Excess bromine is allowed to evaporate, giving pure material, mp 135 °C (50% Br).9

Handling, Storage, and Precautions: protect from moisture, strong acids, and bases. This toxic reagent must be used in a fume hood.

Related Content:

  • Use of Bromine and Bromo-Organic Compounds in Organic Synthesis

    Chemical Reviews

    Saikia, Borah, and Phukan

    2016116 (12), pp 6837–7042

    Abstract: Bromination is one of the most important transformations in organic synthesis and can be carried out using bromine and many other bromo compounds. Use of molecular bromine in organic synthesis is well-known. However, due to the hazardous nature of bromine,...

    Abstract | Full Text HTML | PDF w/ Links | Hi-Res PDF

  • Pyridinium Hydrobromide Perbromide:  A Versatile Catalyst for Aziridination of Olefins Using Chloramine-T

    Organic Letters

    Ali, Nikalje and Sudalai

    19991 (5), pp 705–707

    Abstract: Pyridinium hydrobromide perbromide (Py·HBr3) catalyzes effectively the aziridination of electron-deficient as well as electron-rich olefins using Chloramine-T (N-chloro-N-sodio-p-toluenesulfonamide) as a nitrogen source to afford the corresponding ...

    Abstract | Full Text HTML | PDF w/ Links | Hi-Res PDF

  • NMR Chemical Shifts of Trace Impurities: Common Laboratory Solvents, Organics, and Gases in Deuterated Solvents Relevant to the Organometallic Chemist

    Organometallics

    Fulmer, Miller, Sherden, Gottlieb, Nudelman, Stoltz, Bercaw and Goldberg

    201029 (9), pp 2176–2179

    Abstract: Tables of 1H and 13C NMR chemical shifts have been compiled for common organic compounds often used as reagents or found as products or contaminants in deuterated organic solvents. Building upon the work of Gottlieb, Kotlyar, and Nudelman in the Journal ...Tables of 1H and 13C NMR resonances for common organic contaminants are reported in 12 different deuterated organic solvents frequently used to study organometallic systems. This manuscript catalogs the chemical shifts for nearly 60 gases and organic compounds which are commonly used as reagents or internal standards or are found as products in organometallic reactions.

    Abstract | Full Text HTML | PDF w/ Links | Hi-Res PDF

  • NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities

    The Journal of Organic Chemistry

    Gottlieb, Kotlyar and Nudelman

    199762 (21), pp 7512–7515

    Abstract | Full Text HTML | PDF w/ Links | Hi-Res PDF

  • The use of pyridinium bromide perbromide for brominations.

    Journal of Chemical Education

    Merker and Vona

    194926 (11), p 613

    Abstract | PDF w/ Links | Hi-Res PDF

  • Brominations with Pyridine Hydrobromide Perbromide

    Journal of the American Chemical Society

    Djerassi, Scholz

    194870 (1), pp 417–418

    Abstract | Hi-Res PDF

  • 0 thoughts on “Pyridinium Bromide Perbromide Synthesis Essay”

      -->

    Leave a Comment

    Your email address will not be published. Required fields are marked *