Ethyl acetate, ammonolysis

I) Ammonolysis of Esters. (1) To 5 ml of saturated solution of ammonia in methanol add 2 ml of ethyl acetate. Cork, and allow to stand until the next laboratory period. Place the contents of the tube in an evaporating dish and evaporate the alcohol over a water bath. Determine the weight of the amide. 

Thus, as shown in Scheme 14.7, the reaction of ethyl formate with ethyl acetate in ether in the presence of sodium metal yielded ethyl sodium formyl acetate. Then, the addition product of ethyl bromide with thiourea was treated with aqueous base and the ethyl sodium formyl acetate was added so that, after standing for a number of hours, acidification with acetic acid yielded 2-ethylmercapto-6-oxypyrimidine. Treatment of the latter with phosphorus pentachloride yielded the corresponding 2-ethylmercapto-6-chloropyrimidine subsequent alcoholic ammonolysis generated 2-ethylmercapto-6-aminopyrimidine and boiling aqueous hydrobromic acid resulted in the production of 6-amino-2-oxypyrimidine (cytosine). 

Two new alkaloids have been isolated from Burley tobacco Nicotiana tabacum L.) condensate, and their structures elucidated mainly on mass and n.m.r. spectral evidence. Structure (38) has been assigned to one and confirmed by two syntheses, one of which involves the exhaustive aeetylation of isophorone (39) with aeetie anhydride-perchlorie acid to the pyrylium salt (40). Ammonolysis of the salt yielded the alkaloid (38). The second alkaloid, formulated as (41), was synthesized from 5,5-dimethyl-2-cyclopenten-l-one (42) via Michael addition of ethyl acetoacetate to give, after hydrolysis and decarboxylation, (43). Regioselective acetalization then... 

Sato and Noyori published two syntheses for homopyrazofurin (311) (79H141 83BCJ2700), the most recent of which used the C-glycosylpyruvic ester 181 (Section VI,C Scheme 34), which reacted with ethyl hydrazino-acetate to give 310 followed by ammonolysis and deprotection to 311 (Scheme 68). 

---