Bromotoluenes

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Bromotoluenes
Surname 2-bromotoluene 3-bromotoluene 4-bromotoluene
other names o -bromotoluene m -bromotoluene p -bromotoluene
Structural formula Structure of 2-bromotoluene Structure of 3-bromotoluene Structure of 4-bromotoluene
CAS number 95-46-5 591-17-3 106-38-7
PubChem 7236 11560 7805
Molecular formula C 7 H 7 Br
Molar mass 171.04 g mol −1
Physical state liquid firmly
Melting point −27 ° C −40 ° C 28-29 ° C
boiling point 180 ° C 184 ° C 184 ° C
GHS
labeling
07 - Warning 09 - Dangerous for the environment
Caution
02 - Highly / extremely flammable 07 - Warning
Caution
07 - Warning
Caution
H and P phrases 302-411 226-302-315-319-335 302-315
no EUH phrases no EUH phrases no EUH phrases
273 261-305 + 351 + 338 no P-phrases

The bromotoluenes (more precisely monobromotoluenes) form a group of substances in chemistry that is derived from both toluene and bromobenzene . The structure consists of a benzene ring with attached methyl group  (–CH 3 ) and bromine  (–Br) as substituents . Due to their different arrangement, there are three constitutional isomers with the empirical formula C 7 H 7 Br in addition to benzyl bromide .

presentation

The bromotoluenes can be prepared from the toluidines by means of the Sandmeyer reaction . A mixture of 2- and 4-bromotoluene is obtained by bromination of toluene with bromine and iron , iron (III) bromide being formed as a Lewis acid .

properties

The boiling points of the bromotoluenes are almost the same. The melting points, however, differ more clearly. The 4-bromotoluene, which has the highest symmetry, has the highest melting point and is solid at room temperature.

According to Antoine, the vapor pressure functions result from log 10 (P) = A− (B / (T + C)) (P in bar, T in K) as follows:

Vapor pressure functions of bromotoluenes
T (K) A. B. C.
2-bromotoluene 297.5-454.9 3,91296 1440.879 −85.87
3-bromotoluene 289.9-456.8 6.51377 3506,406 82.744
4-bromotoluene 283.4-457.6 6.40475 3516.111 92.523

Individual evidence

  1. ↑ a b c Entry on 2-bromotoluene in the GESTIS substance database of the IFA , accessed on December 27, 2014(JavaScript required) .
  2. ↑ a b c Entry on 3-bromotoluene in the GESTIS substance database of the IFA , accessed on December 27, 2014(JavaScript required) .
  3. ↑ a b CRC Handbook of Tables for Organic Compound Identification , Third Edition, 1984, ISBN 0-8493-0303-6 .
  4. ↑ Data sheet 4-Bromotoluene from Sigma-Aldrich , accessed on December 27, 2014 ( PDF ).
  5. ^ Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 566.
  6. ↑ Stull, DR: Vapor Pressure of Pure Substances Organic Compounds , in: Ind. Eng. Chem. 39 (1947) 517-540, doi: 10.1021 / ie50448a022 .