A synthetic method that relies on gold-catalysed cyclopropyl carbinol rearrangement of 2-tosylaminophenyl cyclopropylmethanols to prepare 2,3-dihydro-1H-benzo[b]azepines and 2-vinylindolines efficiently is reported. The reactions were shown to be chemoselective, with secondary and tertiary alcohol substrates exclusively providing benzo-fused five- and seven-membered ring products, respectively. The ring-forming process was also found to proceed in moderate to excellent yields under mild conditions only in the presence of the gold and silver catalyst combination. The mechanism is thought to involve activation of the alcohol by the (p-CF(3)C(6)H(4))(3)PAuCl/AgOTf (Tf = triflate) catalyst, resulting in ionization of the starting material. The tertiary carbocationic intermediate generated in situ in this manner then triggers ring-opening of the cyclopropane moiety and trapping by the tethered aniline group to give the 2,3-dihydro-1H-benzo[b]azepine. Cyclopropane ring fragmentation of the secondary carbocationic analogue, on the other hand, results in diene formation followed by subsequent intramolecular hydroamination to afford the 2-vinylindoline.

The effects of starting material substitution patterns on reaction selectivity for the gold(I)-catalysed cycloisomerisations of aryl substituted 1,7-enynes were investigated. The results indicated the chemoselectivity of the reaction to be highly substrate and catalyst dependent. Either the piperidine or the tetrahydro-1H-azepine product was obtained in moderate to excellent yields depending on the steric and/or electronic nature of the substrate and the gold(I) catalyst. Overall, six-membered nitrogen ring formation was found to be favoured in reactions with 1,7-enyne derivatives containing a disubstituted alkene moiety or not bearing a sterically bulky substituent or a gold(I) catalyst with a pendant sterically unencumbered phosphine ligand. Formation of the seven-membered nitrogen heterocycle was observed in reactions where the substrate contained a tetrasubstituted alkene unit or a sterically demanding substituent.

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Review question / Objective: How do PDT and lasers affect the clinical results of nonsurgical treatment in patients with periimplant diseases? Does PDT and lasers, when used as an adjunctive treatment, provide superior clinical and patientpreferred outcomes compared with nonsurgical mechanical debridement in patients with peri-implant diseases? What was the rankings on the effect of PDTs and different lasers as an non-surgical INPLASY 1

Study of Substrate Dependence on the Chemoselectivity of the Gold-Catalyzed Cycloisomerization of Aryl Substituted 1,7-Enynes. -The substitution pattern of the starting material as well as the steric and electronic nature of the gold catalyst influence the chemoselectivity of this cycloisomerization. -(HUANG, C.; KOTHANDARAMAN, P.; KOH, B. Q.; CHAN*, P. W. H.; Org. Biomol. Chem. 10 (2012) 45, 9067-9078, http://dx.doi.org/10.1039/c2ob26458g ; Div. Chem. Biol. Chem., Sch. Phys. Math. Sci., Nanyang Technol. Univ., Singapore 637371, Singapore; Eng.) -Roessler 19-155