Synthesis of ketones from iodoalkenes, carbon monoxide and 9-alkyl-9-borabicyclo[3.3.1]nonane derivatives via a radical cyclization and palladium-catalysed carbonylative cross-coupling sequence
Under irradiation (tungsten lamp), the palladium-catalysed three-component cross-coupling reaction between iodoalkenes such as 6-iodo-1-hexene or their derivatives, carbon monoxide (1 atm) and 9-alkyl- or 9-aryl-9-BBN derivatives (9-BBN = 9-borabicyclo[3.3.1]nonane) produces unsymmetrical ketones in moderate to high yields; the oxidative addition of iodoalkenes to a palladium(0) complex proceeds via a radical process, thus allowing cyclization of the iodoalkenes to five-membered rings prior to the couplings with carbon monoxide and boron reagents.
The first catalytic asymmetric intramolecular 1,6-C–H insertion reaction of α-diazo esters is described. With dirhodium(II) tetrakis[N-phthaloyl-(S)-tert-leucinate], Rh2(S-PTTL)4, the C–H insertion proceeded in a chemoselective manner to give 2-alkenyltetrahydropyran-3-carboxylates with up to 95% ee and perfect cis diastereoselectivity.
Alkyl iodides 1-5 react with xenon difluoride with loss of iodide and incorporation of fluorine. A carbocationic intermediate undergoes cyclization with an internal olefinic function. (C) 1997 Elsevier Science Ltd.
SMALL MOLECULE LIGAND-DRUG CONJUGATES FOR TARGETED CANCER THERAPY
申请人:Chung Leland W.K.
公开号:US20110085974A1
公开(公告)日:2011-04-14
The present invention describes small molecule ligand-drug conjugates and methods of using the small molecule ligand-drug conjugates for targeted treatment of cancer in a patient in need thereof. Further described are methods of sterilizing circulating tumor cells and determining drug concentration in cancer tissue.