Acetic-formic anhydride

Attempts to use acetic-formic anhydride with Friedel-Crafts catalysts resulted only in acetylation. However, using anhydrous HF as a catalyst, a small amount of aldehyde is also formed in accordance with the fact that acetic—formic anhydride gives both acetyl and formyl fluoride with HF. By continuous removal of the low boiling HCOF, the reaction can be shifted to the formation of this compound (118). 

Acetic acid, (3,5,6-trichloro-2-pyridinyloxy)-as herbicide, 2, 513 Acetic formic anhydride... 

Typically, the K-R reaction is run at temperatures that often exceed 160 "C. However, a mild variation has been developed using acetic formic anhydride where the transformation occurs at ambient temperature. Okumara and coworkers smoothly converted hydroxyl ester 25 to chromone 26 in 76% yield with acetic formic anhydride and sodium formate at room temperature.Beckett and Ellis also used these conditions to synthesize two chromones in high yield when 27 and 28 were converted to 29 and 30, respectively. ... 

In the course of synthesizing DNA-gyrase inhibitors Hogberg, Mitscher, and coworkers determined that an effective means of constructing the core of their inhibitors was via a K-R reaction. Under mild conditions, keto ethylester 52 was acylated using acetic formic anhydride in the presence of sodium formate to deliver chromone 53 in 75% yield. 

The scope of this reaction is similar to that of 10-21. Though anhydrides are somewhat less reactive than acyl halides, they are often used to prepare carboxylic esters. Acids, Lewis acids, and bases are often used as catalysts—most often, pyridine. Catalysis by pyridine is of the nucleophilic type (see 10-9). 4-(A,A-Dimethylamino)pyridine is a better catalyst than pyridine and can be used in cases where pyridine fails. " Nonbasic catalysts are cobalt(II) chloride " and TaCls—Si02. " Formic anhydride is not a stable compound but esters of formic acid can be prepared by treating alcohols " or phenols " with acetic-formic anhydride. Cyclic anhydrides give monoesterified dicarboxylic acids, for example,... 

The hydrochloride salt of 4-amino-1-benzylimidazole (83 R = H) was acetylated readily by acetic anhydride to give the acetamide derivative (83 R = COCHj) (55%) (74JMC1168). Treatment with acetic-formic anhydride gave the corresponding formamide (83 R = CHO). 

Acetic anhydride, with 2-hep-tanone to give 3-n-butyl-2, 4-pentanedione, 51, 90 ACETIC FORMIC ANHYDRIDE, 50, 1 Acetone azine, 50, 2 ACETONE HYDRAZONE, 50, 2, 28 Acetophenone, 54, 93 as sensitizer for irradiation of bicyclo[2.2.1]hepta-2,5-diene to give quadricyclane,... 

FORMATION AND PHOTOCHEMICAL WOLFF REARRANGEMENT OF CYCLIC a-DIAZO KETONES D-NORANDROST-5-EN-3 -0L-16-CARB0XYLIC ACIDS, 52, 53 FORMIC ACID, AZIDO—, tert-BUTYL ESTER, 50, 9 Formylation, with acetic formic anhydride, 50, 2 p-FORMYLBENZENESULFONAMIDE, ... 

Reaction of hydroxy lactam 97 with acetic formic anhydride gives the formyl derivative 98 in high yield <20000L99>. 

The hydroxyquinoline (39-2) provides the starting material for a quinolone that incorporates a hydrazine function. Reaction of (39-2) with 2,4-dintrophenyl O-hydroxylamine ether (41-1) in the presence of potassium carbonate leads to a scission of the weak N-O hydroxylamine bond by the transient anion from the quinolone the excellent leaving character of 2,4-dinitrophenoxide adds the driving force for the overall reaction, resulting in alkylation on nitrogen to form the hydrazine (41-2). The primary amine is then converted to the formamide (41-3) by reaction with the mixed acetic-formic anhydride. Alkylation of that intermediate with methyl iodide followed by removal of the formamide affords the monomethylated derivative (41-4). Chlorine at the 7 position is then displaced by A-methylpiperazine and the product saponified. There is thus obtained amifloxacin (41-6) [48]. 

Fife Zhang J. Org. Chern. 1986, 51, 3744. See also Fife Zhang Tetrahedron Leu. 1986, 27, 4933, 4937. For a review of acetic formic anhydride see Strazzolini Giumanini Cauci Tetrahedron 1998, 46 1081-1118. 

Treatment of potassium isatinate with sodium formate in acetic-formic anhydride gave 1-formylisatin,98 while the sodium isatinate 23 was cyclized by treatment with acid to the expected 5-substituted isatin.99... 

The synthesis of the nucleoside 594 was performed by the reaction of the hydrazino derivatives 593 with acetic anhydride at room temperature. Deacetylation of 594 gave (2-deoxy-/3-D-ribofuranosyl)triazolopyrimidine (595). Reaction of 593 with acetic formic anhydride in dry pyridine followed by treatment with ammonia/MeOH gave the triazolo[4,3-c]pyrimi-dine nucleoside 596 (91MI4) (Scheme 118). 

The use of the very reactive mixed acetic formic anhydride at room temperature allows the synthesis of chromones unsubstituted at C-2. Especially good yields result when an electron-withdrawing group is present in the acyl moiety of the ketone <78JCR(M)0865>. 

Tin(II) chloride, 298 to other nitrogen compounds Borane-Tetrahydrofuran, 42 Tin(II) chloride, 298 of nitrogen compounds, but not nitriles and nitro compounds Acetic-formic anhydride, 1 Borane-Dimethylamine, 42 Palladium catalysts, 230 Trimethylsilyllithium-Hexamethyldisi-lane, 328... 

Sodium hydrogen telluride, 282 Tin(II) chloride, 298 By other methods Acetic-formic anhydride, 1 Arene(tricarbonyl)chromium complexes, 19... 

Prior to this report the only known formyl complex had been Fe(CO)4-(CHO) synthesized by Collman and Winter from Fe(CO)4 and acetic formic anhydride (59). 

Formylation. The anhydride formylates even unstable amines in an alcohol-free solvent in 80-100% yield. In no cases are even traces of trimethylacetamides detectable. Substantial amounts of acetamides can be formed when acetic formic anhydride is used. 

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