Bechamp reaction
{{Short description|Chemical reaction}}
{{For|Bechamp reduction of aromatic nitro compounds|Bechamp reduction}}
In organic synthesis the Béchamp reaction is used for producing arsonic acids from activated aromatic substrates. The reaction is an electrophilic aromatic substitution, using arsenic acid as the electrophile. The reaction proceeds according to this idealized stoichiometry for the preparation of arsanilic acid:{{Ullmann |doi=10.1002/14356007.a03_113.pub2|title=Arsenic and Arsenic Compounds |year=2008 |last1=Grund |first1=Sabina C. |last2=Hanusch |first2=Kunibert |last3=Wolf |first3=Hans Uwe |isbn=978-3527306732 }}
:{{chem2|C6H5NH2 + H3AsO4 -> H2O3AsC6H4NH2 + H2O}}
Reaction scope
The reaction was first reported in 1863 by Antoine Béchamp.{{cite journal | url=http://gallica.bnf.fr/ark:/12148/bpt6k3013s/f1172.item.r= | title=de l'action de la chaleur sur l'arseniate d'analine et de la formation d'un anilide de l'acide arsenique | author=M. A. Bechamp | journal=Compt. Rend. | year=1863 | volume=56 | pages=1172–1175}}{{cite journal|author1=C. S. Hamilton |author2=J. F. Morgan |name-list-style=amp |doi=10.1002/0471264180.or002.10|journal= Organic Reactions|year=1944|page=2|title=The Preparation of Aromatic Arsonic and Arsinic Acids by the Bart, Bechamp, and Rosenmund Reactions|isbn=0471264180}} It is very analogous to the sulfonation of arenes.
The Béchamp reaction was employed in the Nobel Prize-winning work on organoarsenicals by Paul Erlich.{{cite journal|author1=P. Ehrlich |author2=A. Bertheim |name-list-style=amp |journal=Chemische Berichte|year=1907|volume=40|page= 3292|doi=10.1002/cber.19070400397|title=Überp-Aminophenylarsinsäure|issue=3|url=https://zenodo.org/record/1426249}}
In one commercial application, the Béchamp reaction is reaction is used to produce roxarsone, which exhibits an anticoccidial action and promotes growth in animals.{{cite journal|author1=John F. Stolz |author2=Eranda Perera |author3=Brian Kilonzo |author4=Brian Kail |author5=Bryan Crable |author6=Edward Fisher |author7=Mrunalini Ranganathan |author8=Lars Wormer |author9=Partha Basu |name-list-style=amp |title=Biotransformation of 3-Nitro-4-hydroxybenzene Arsonic Acid (Roxarsone) and Release of Inorganic Arsenic by Clostridium Species|journal= Environ. Sci. Technol.|year= 2007|volume= 41|issue=3|pages= 818–823|doi= 10.1021/es061802i|pmid= 17328188|bibcode=2007EnST...41..818S}}
Further reading
- {{cite journal|author1=H. P. Brown |author2=C. S. Hamilton |name-list-style=amp |journal=J. Am. Chem. Soc.|year=1934|volume=56|page= 151|doi=10.1021/ja01316a047|title=Naphthalenearsonic Acids. The Application of the Béchamp Reaction to α-Naphthylamine}}