Jens Ahman

John P. Wolfe; Jens Ahman; Joseph P. Sadighi; Robert A. Singer; Stephen L. Buchwald

Abstract Commercially available benzophenone imine serves as a convenient ammonia equivalent in the palladium-catalyzed amination of aryl halides and triflates. The benzophenone imine adducts can be cleaved directly to the corresponding primary anilines by catalytic hydrogenation or treatment with hydroxylamine hydrochloride or a catalytic amount of HCl in wet THF.

Peter Somfai; Jens Ahman

Abstract A short and enantioselective total synthesis of the neurotoxic alkaloid (+)-Anatoxin-a ( 1 ) from the L-pyroglutamic acid derivative 2 is described. The key step involves an intramolecular cyclisation of an N-tosyl iminium ion derived from the corresponding α-methoxy sulfonamide.

Jens Ahman; Peter Somfai

Abstract A mild and efficient procedure for N-alkylation of 2,3-trans-disubstituted aziridines by using K2CO3/18-crown-6 as base is described.

Jens Ahman; Peter Somfai; David Tanner

The thermal 1,5-hydrogen shift of the enantiomerically pure vinyl aziridines 1 yields allylic imines 3 in quantitative yields and as single diastereomers.

Jens Ahman; Peter Somfai

Cyclic N-sulfonylenamines can be prepared under mild conditions from the corresponding lactams by an efficient two-step procedure involving diisobutylaluminium hydride (DIBAL) or LiAIH4 reduction followed by CF3CO2H induced dehydration. In addition, appropriately substituted N-sulfonylenamines are substrates in intramolecular radical cyclizations, forming the corresponding spirocyclic sulfonamides in good yields.

Jens Ahman; John P. Wolfe; Malisa V. Troutman; Michael Palucki; Stephen L. Buchwald

Takayuki Hamada; Andre Chieffi; Jens Ahman; Stephen L. Buchwald

Andre Chieffi; Ken Kamikawa; Jens Ahman; Joseph M. Fox; Stephen L. Buchwald

Jens Ahman; Stephen L. Buchwald

Stephen L. Buchwald; David W. Old; John P. Wolfe; Michael Palucki; Ken Kamikawa; Andrew Chieffi; Joseph P. Sadighi; Robert A. Singer; Jens Ahman