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A novel rhodium-catalyzed intermolecular direct C—H olefinic allylation of electron-deficient alkenes with easily available allyl acetates as electrophiles is developed.

The synthetic utility of the methodology is demonstrated by the representative derivatization of one product [cf.

Rh(III)-catalyzed C–H olefinic alkynylation of enamides for the stereospecific construction of synthetically useful Z-type enynamides is reported. This protocol displays good functionality tolerance and operational simplicity thus providing an alternative synthetic opportunity for the ease of access to specific 1,3-enyne derivatives.

A novel cationic Rh(III)-catalyzed olefination of N,N-dialkylbenzamides with allylic acetates is developed to give trans-olefins in good yields.

Novel and facile routes to alkenyl, alkynyl, and aryl 1,2-diketones utilize treatment of benzotriazole derivatives 1, 7a,b, and 15a−d with butyllithium and subsequent reaction with esters or acid chlorides to yield the substituted intermediates 2a−d, 8a,b, and 16a−g. Reactions of the deprotonated 1 and 7 with α,β-unsaturated aldehydes followed by oxidation also produces similar intermediates 5 and 11a,b. Subsequent hydrolyses of the intermediates of type 2, 5, 8, 11, and 16 afford diverse 1,2-diketones in good yields.

C−Benzotriazole bonds were selectively transformed to give the corresponding α-aminocarbanions when N-(α-aminoalkyl)benzotriazoles were reacted with either Li/LiBr or SmI2 in the presence of representative electrophiles. The ranges of applicability of the two reagents complement each other, and together the two protocols provide a general route from readily available crystalline starting materials to a variety of “nonstabilized” α-aminocarbanions that can be trapped in moderate to good yields.

Tosylmethylamines (1) are advantageous synthon equivalents for “nonstabilized” α-aminocarbanions of aromatic amines. Clean reactions and high yields are observed provided one-step procedures are ut...

1-(α-Alkoxyalkyl)benzotriazoles 1a−d add to phenyl vinyl ether to form key intermediates 4a−d, which readily undergo lithiation and subsequent trapping by a variety of electrophiles to give the expected substituted derivatives 7a−d, 9a−c, 11, 13, 15, and 18 in high yields. Subsequent hydrolysis of these compounds provides a novel high-yield acyl anion synthon approach for the synthesis of β-alkoxy ketones 8 or α‘-functionalized β-alkoxy ketones 10, 12, 14, 16, and 19 by short procedures from readily available starting materials.

A variety of 3,5-substituted 1,3-oxazolidines are synthesized from primary amines by a novel, two step sequence.

1,2,4-Triazole stabilized allene anions are intermediates for the synthesis of 4-alkyl-2(5H)-thiophenones and 8-phenylimino-1,2,4-triazolo[5,1-c]-1,4-thiazines. Structures are confirmed by X-ray cr...

Polysubstituted piperidines were prepared via radical cyclization of α-aminoalkyl radicals onto unactivated double bonds. [1,2]-aza-Wittig rearrangements were observed when an aryl group was attached to the α-aminoalkyl radical center.