Medium-sized lactam

A combination of N and CO activation was used by Vilarrasa to generate a range of medium-sized lactams 56. m-Azido carboxylic acids 54 were initially... 

The synthesis of medium-sized lactams 100 has been attempted by means of amine-directed carbonylation of 5-iST-benzylamino-l-pentene 97. In presence of... 

Samarium(n) iodide reduction of benzothiazinium salt 87d at room temperature gave exclusively formation of the medium-sized lactam sulfide 89d, as shown in Equation (23) <1997J(P1)309>. 

Hydrogen abstraction under conditions similar to those in Section 3.8.1 may occur also from nitrogen compounds, with formation of amidyl free radicals. The results vary, depending on the substrate for example, 6-amino derivatives of steroids were converted into TV-substituted pyrrolidines [127], Medium-sized lactams underwent transannular cyclization to bicyclic lactams [128], and bicyclic carbinolamides afforded mainly -fragmentation products (Table 3.7). 

Amines lactams. Simple acyloxyboranes are known to react with amines to form amides, but in low yield. This reaction has been improved by use of catecholborane (equation I). It can be extended to synthesis of lactams. Thus addition of catecholborane to a suspension of an w-amino acid in pyridine (80°) results in a lactam. Yields are high (85-95%) for 3- and 5-membered lactams. Yields are low (—6 (.) in the case of medium-size lactams, but improve to 10-15% in the synthesis of 14- and 16-mcmbcrcd lactams. (Dimers are formed preferentially.) Yields are... 

David O, Meester WJN, Bieraugel H, Schoemaker HE, Hiemstra H, van Maarseveen JH. Intramolecular staudinger ligation a powerful ring-closure method to form medium-sized lactams. Angew. Chem. Int. Ed. 2003 42 4373-4375. 

Dorta, R. L., Francisco, C. G., Suarez, E. Hypervalent organoiodine reagents in the transannular functionalization of medium-sized lactams synthesis of 1-azabicyclo compounds. J. Chem. Soc., Chem. Common. 1989,1168-1169. 

Gerard B, Duval JR, Lowe JT, et al. Synthesis of a stereochemically diverse library of medium-sized lactams and sultams via S(N)Ar cycloetherification. ACS Comb Sci 2011 13 365-374. 

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