Effets de cryptands et activation de bases—Va

Direct cycle between co-product and reactant: an approach to improve the atom economy and its application in the synthesis and protection of primary amines

“…12,13 To circumvent the long-standing problems that have limited the widespread application of the Gabriel synthesis, modifications of the original Gabriel synthesis, including the addition of catalysts, hydrazinolysis for the cleavage of the N-alkylphthalimide and new Gabriel reagents, have been reported. [14][15][16][17][18] It is necessary and important to improve the yields of every step within the Gabriel synthesis, including the alkylation of phthalimide and the hydrolysis of the resulting N-alkylphthalimide. In our opinion, however, an efficient recovery of the phthalyl co-products after hydrolysis or hydrazinolysis and reapplying them in the same reaction is the key to an atom-economical Gabriel-type amine synthesis.…”

Evaluation of N‐Hydroxymethylphthalimide in Alkaline Medium: Novel Entry to the Tricyclic [1,3]Oxazepine Core via an Intramolecular π and O‐Cationic Cyclization.

“…Attempts to extend this reaction to heteroaromatic, alkyl, functionalized alkyl, functionalized aromatic and functionalized heteroaromatic halides was successful and produced only the corresponding N-alkylated products 9b (75%) [18], 9c (49%) [19], 9d (58%) [20], 9e (69%) [21], and 9f (71%) [21], respectively. In light of these results, its seems that the imidate anion D is more stable than the alcoholate one C under basic conditions at these temperatures.…”