Hydrazide#Acyl hydrazides
{{Short description|Class of chemical compounds}}
Hydrazides in organic chemistry are a class of organic compounds with the formula {{chem2|R\sNR^{1}\sNR^{2}R^{3}|}} where R is acyl ({{chem2|R'\sC(\dO)\s}}), sulfonyl ({{chem2|R'\sS(\dO)2\s}}), phosphoryl ({{chem2|(R'\s)2P(\dO)\s}}), phosphonyl ({{chem2|(R'\sO\s)2P(\dO)\s}}) and similar groups (chalcogen analogs are included, for example sulfur analogs called thiohydrazides),{{cite web | website=chem-space.com|title=Search | url=https://chem-space.com/search/bb/exact/NNC%2528%253DS%2529c1ccccc1/004388e764d06aa0359aa04977357ef0 | access-date=24 May 2023}} (subscription required) {{chem2|R^{1}, R^{2}, R^{3}|}} and R' are any groups (typically hydrogen or organyl).{{GoldBookRef|file=H02879|title=Hydrazides}} Unlike hydrazine and alkylhydrazines, hydrazides are nonbasic owing to the inductive influence of the acyl, sulfonyl, or phosphoryl substituent.
Sulfonyl hydrazides
A common sulfonyl hydrazide is p-toluenesulfonyl hydrazide, a white air-stable solid. They are also widely used as organic reagents.
Toluenesulfonyl hydrazide is used to generate toluenesulfonyl hydrazones. When derived from ketones, these hydrazones participate in the Shapiro reaction{{cite journal|last = Shapiro|first = Robert H.|authorlink = Robert H. Shapiro|title = Alkenes from Tosylhydrazones|journal = Org. React.|year = 1976|volume = 23|issue = 3|pages = 405–507|doi = 10.1002/0471264180.or023.03|isbn = 0471264180}} and the Eschenmoser–Tanabe fragmentation.{{cite journal|first1 = J.|last1 = Schreiber|first2 = D.|last2 = Felix|first3 = A.|last3 = Eschenmoser|authorlink3 = Albert Eschenmoser|first4 = M.|last4 = Winter|first5 = F.|last5 = Gautschi|first6 = K. H.|last6 = Schulte-Elte|first7 = E.|last7 = Sundt|first8 = G.|last8 = Ohloff|authorlink8 = Günther Ohloff|first9 = J.|last9 = Kalovoda|first10 = H.|last10 = Kaufmann|first11 = P.|last11 = Wieland|first12 = G.|last12 = Anner|title = Die Synthese von Acetylen-carbonyl-Verbindungen durch Fragmentierung von α,β-Epoxy-ketonen mit p-Toluolsulfonylhydrazin. Vorläufige Mitteilung|year = 1967|journal = Helv. Chim. Acta|language = German|volume = 50|issue = 7|pages = 2101–2108|doi = 10.1002/hlca.19670500747}}{{cite journal|first1 = Masato|last1 = Tanabe|authorlink1 = Masato Tanabe|first2 = David F.|last2 = Crowe|first3 = Robert L.|last3 = Dehn|title = A novel fragmentation reaction of α,β-epoxyketones the synthesis of acetylenic ketones|journal = Tetrahedron Lett.|year = 1967|volume = 8|issue = 40|pages = 3943–3946|doi = 10.1016/S0040-4039(01)89757-4}}
2,4,6-Triisopropylbenzenesulfonylhydrazide is a useful source of diimide.{{cite book |doi=10.1002/047084289X.rt259.pub2|chapter=2,4,6-Triisopropylbenzenesulfonylhydrazide|title=Encyclopedia of Reagents for Organic Synthesis|year=2008|last1=Chamberlin|first1=A. Richard|last2=Sheppeck|first2=James E.|last3=Somoza|first3=Alvaro|isbn=978-0471936237}}
Acyl hydrazides
Acylhydrazines are derivatives of carboxylic acids, although they are typically prepared by the reaction of esters with hydrazine:{{Ullmann|doi=10.1002/14356007.a13_177|title=Hydrazine|year=2001|last1=Schirmann|first1=Jean-Pierre|last2=Bourdauducq|first2=Paul|isbn=3527306730}}
=Use=
An applied example is a synthesis of sunitinib begins by mixing 5-fluoroisatin slowly into hydrazine hydrate.{{cite web|url=http://www.patentlens.net/patentlens/structured.cgi?patnum=US_6573293#show|archive-url=https://archive.today/20120906223144/http://www.patentlens.net/patentlens/structured.cgi?patnum=US_6573293%23show|url-status=dead|archive-date=2012-09-06|title=US patent 6573293}} After 4 hours at 110 °C, the indole ring structure has been broken into (2-amino-5-fluoro-phenyl)-acetic acid hydrazide with reduction of the ketone at the 3-position. Subsequent annelation in strong acid creates the 1,3-dihydro-2-oxo indole structure required for the drug.
See also
- hydrazide imide - tautomeric form of amidrazone
References
{{commons category|Hydrazides}}
{{Reflist}}
{{Hydrazines}}
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