172478-10-3Relevant articles and documents
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Hata,Watanabe
, p. 4659 (1972)
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Reactions of amines and hydrazides derived from L-proline with dialkyl dicyanofumarates
Mloston, Grzegorz,Pieczonka, Adam M.,Wroblewska, Aneta,Linden, Anthony,Heimgartner, Heinz
, p. 343 - 356 (2013/08/15)
The reaction of prolinamine derivatives (8a,b) and dialkyl dicyanofumarates (1) in dichloromethane at room temperature leads to the optically active enamines (10). Whereas products (10) in the case of 1-benzyl prolinamine (8a) are stable compounds, the corresponding enamines obtained from the non-protected prolinamine (8b) smoothly undergo a cyclocondensation at room temperature to give perhydropyrrolo[1,2-a]pyrazine derivatives (11). The molecular structure of 11a was established by X-Ray crystallography. In analogy to 8a, 1-benzyl prolinehydrazide (9a) and 1b in dichloromethane react to yield the enehydrazine (12b). On the other hand, the reaction of 9a and 1 in methanol at room temperature leads to the corresponding dialkyl 3-amino-1H-pyrazole- 4,5-dicarboxylates (13) and methyl 1-benzylprolinate (14b) Via a stepwise mechanism. The analogous reaction was observed between a 3-oxidoimidazole-4- carbohydrazide (15) and 1b.
One-carbon ring expansion of azetidines via ammonium ylide [1,2]-shifts: A simple route to substituted pyrrolidines
Bott, Tina M.,Vanecko, John A.,West
supporting information; scheme or table, p. 2832 - 2836 (2009/08/15)
Simple N-substituted azetidines were heated with diazocarbonyl compounds in the presence of catalytic Cu(acac)2 to furnish substituted pyrrolidines via Stevens [1,2]-shift. In all but two examples, complete selectivity was seen for ring expansion rather than migration of the other exocyclic group on the azetidinium nitrogen. The two exceptions, observed with ylides substituted with two carbonyl groups and lacking a stabilizing group at the 2-position of the azetidine, underwent exocyclic benzyl migration in preference to ring expansion.