Ketones, cyclic, lactams from

KETONE, CONJUGATE ALLYLATION OF a,g-UNSATURATEO. 62, 86 KETONE, a-TERT-AUYLATION, 62. 95 Ketones, a,6-acetylen1c, asymnetrlc reduction, 63, 63 Ketones, cyclic, lactams from, 63, 188 Ketones, e-hydroxy-, synthesis of, 63, 79... 

Synthesis of cyclic azomethines from lactams via (carbalkoxyamino)ketones C... 

Lactams from cyclic amines. A mixture of iodosobenzene and water stirred for 15 min, the slurry cooled to 0°, treated in one portion with pyrrolidine, stirred at 9" for 1 h, then at room temp, until a clear soln. was obtained (4-5 h) - 2-pyrrolidinone. Y 49%. F.e. inch 3,4-dihydroisocarbostyrils and 2-piperidones, also nitriles from prim, amines, and cyclic ketones from cycloalkylamines, s. R.M. Moriarty et al., Tetrahedron Letters 29, 6913-6 (1988) cyclic azomethines in methylene chloride cf. ibid. 6917-20. 

Schiff bases s. Azomethines Schlotterbeck s. Buchner Schmidt reaction 17, 524 —, amines from carboxylic acids 19, 305 20, 366 —, lactams from ketones, cyclic, ring expansion... 

Poly phosphoric acid sodium azide Lactams from cyclic ketones by Schmidt reaction and from cyclic oximes by Beckmann rearrangement Ring expansion... 

Mesitylenesulfony loxylamine/alumina Lactams from cyclic ketones Ring expansion s. 32,285... 

Lactams from cyclic ketones—Electrostatic effects on the Schmidt reaction s. 13, 379 bicyclic lactams s. R. J. Michaels and H. E. Zaugg, J. Org. Ghem. 25, 637 (1960)... 

Poly phosphoric acidinitromethane Lactams from cyclic ketones... 

The first /3 -lactam was produced by addition of a ketene to an imine and there are now many examples of this type of approach. The ketenes are most frequently generated in situ from acid chlorides by dehydrohalogenation, but have also been produced from diazo ketones, by heating of alkoxyacetylenes and in the case of certain cyanoketenes by thermolysis of the cyclic precursors (162) and (163). 

Nine-membered lactam rings can also be produced by the Beckmann rearrangement. The azonane ring 420 was selectively formed from an eight-membered cyclic ketone 419 by a rearrangement/reduction sequence (equation 175). 

An efficient and operationally simple synthesis of tetrahydrofuran-derived spiro-P-lactams 15 and 16 using the Staudinger reaction of unsymmetrical cyclic ketones has been described <02JCS(P1)571 02SL69>. Similarly, spiro-P-lactams 17 were synthesized via Staudinger reaction of imines derived from 7-oxanorbomenone with alkoxyacetyl chlorides <02TL6405>. 

HCl-HOAc-AcjO, POCls, BiCla, neat with FeCls, and polyphosphoric acid. The reaction has been done in supercritical water and in ionic liquids. A polymer-bound Beckman rearrangement has been reported. Sim-ply heating the oxime of benzophenone neat leads to A-phenyl benzamide. The oximes of cyclic ketones give ring enlargement and form the lactam,as in the formation of caprolactam (83) from the oxime of cyclohexanone. Heating an... 

The applications of ruthenium tetroxide range from the common types of oxidations, such as those of alkenes, alcohols, and aldehydes to carboxylic acids [701, 774, 939, 940] of secondary alcohols to ketones [701, 940, 941] of aldehydes to acids (in poor yields) [940] of aromatic hydrocarbons to quinones [942, 943] or acids [701, 774, 941] and of sulfides to sulfoxides and sulfones [942], to specific ones like the oxidation of acetylenes to vicinal dicarbonyl compounds [9JS], of ethers to esters [940], of cyclic imines to lactams [944], and of lactams to imides [940]. 

The Schmidt reaction is closely related to the Beckmann reaction (equation 34). Acyclic and cyclic ketones are transformed to amides and lactams by treatment with hydrogen azide. With bridged bi-cyclic ketones, the regioselectivity of the migration is opposite to the direction of the Beckmann reaction. The Schmidt reaction has been applied to asymmetric synthesis starting from optically active a,a-dialkylated -keto esters. High chemical and optical yields have been obtained (equation 35). ... 

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