Aniline neutral moiety

Rather unusually, a method has been developed for the photoprotection of amines using the N-benzyloxycarbonyl (iV-Cbz) and N-9-fluorenylmethoxycar-bonyl (iV-Fmoc) derivatives of 5,7-dinitroindoline (51) and (52). ° These reagents allow efficient protection of primary and secondary amines as carbamate (iV-Cbz or N-Fmoc) derivatives in neutral conditions, by UV irradiation (350 nm) of a mixture of the amine with either (51) or (52). It is possible, moreover, to premix the reagents and then photolytically trigger the acylation reaction later. The mechanism of the overall protection reaction does not appear to have been determined, but formally it involves photorelease of the Cbz or Fmoc moiety from the indoline. Bulky amines and anilines gave low yields or no product, and... 

The Buchwald series of bulky phosphines containing the tunable bi-aryl moiety have also been shown to allow for the efficient animation of aryl chlorides as well.57 In particular, Pd/L3 catalyzed the reaction between secondary cyclic amines and most aryl chlorides at 80 °C, Secondary acyclic amines and anilines tend to couple best with neutral to electron rich aryl chlorides. Primary aliphatic amines are quite limited to either the amination of o-tolyl chlorides, or more activated primary amines such as benzyl amine. A better ligand for this transformation was reported to be L4 as the amination could be conducted at room temperature in many cases.58 Base sensitive R1 required the use of K3PO4 rather than NaOf-Bu. Most amines work well with this catalyst system, except for unactivated primary aliphatic amines (e.g., n-hexyl amine). Allyl amine, hydrazines, imines, benzyl amine, and (EtO)2CH2NH2 all couple well with aryl chlorides under the... 

---