- Carbonyl 1,2-transposition through triflate-mediated a-amination
-
To date, it remains challenging to selectively migrate a carbonyl oxygen within a given molecular scaffold, especially to an adjacent carbon. In this work, we describe a simple one- or two-pot protocol that transposes a ketone to the vicinal carbon. This approach first converts the ketone to the corresponding alkenyl triflate, which can then undergo the palladium- and norbornene-catalyzed regioselective a-amination and ipso-hydrogenation enabled by a bifunctional hydrogen and nitrogen donor. The resulting "transposed enamine" intermediate can subsequently be hydrolyzed to produce the 1,2-carbonyl-migrated product. This method allows rapid access to unusual bioactive analogs through late-stage functionalization.
- Wu, Zhao,Xu, Xiaolong,Wang, Jianchun,Dong, Guangbin
-
p. 734 - 740
(2021/11/16)
-
- Synthesis of the 5-Thiorotenoid System from Thiochroman-3-one
-
Base-induced cyclisation of the diketones 10 (X = H or F), prepared in a two-step sequence from thiochroman-3-one, affords 6H,12H-benzothiopyranobenzopyran-12-ones 11.Reduction with diisobutylaluminium hydride affords a separable mixture of t
- Gabbutt, Christopher D.,Hepworth, John D.,Heron, B. Mark
-
p. 3015 - 3018
(2007/10/02)
-
- Enamino Ketones as Precursors of Functionalised 2H-Thiopyrans and Thiopyrano- and -benzothiopyrans
-
Oxo enamino ketones obtained by treating active methylene compounds with N,N-dimethylformamide dimethyl acetal yield novel 2H-thiopyrans in a regioselective one pot thionation--cycloaddition sequence.Application of similar methodology to thiochroman-3-ones affords novel thiopyranobenzothiopyrans and the isomers.
- Gabbutt, Christopher D.,Hepworth, John D.,Heron, B. Mark
-
p. 2603 - 2608
(2007/10/02)
-
- CONFORMATIONAL AND STERIC REQUIREMENTS OF THE SIDE CHAIN FOR SULPHUR PARTICIPATION IN BENZTHIEPIN DERIVATIVES
-
Attempted ring expansion of some benzthiepin derivatives resulted in the formation of benzthiophens such as (3a,b) and (3d,e).A probable mechanism for this tansformation has been presented.
- Patra, Ranjan,Ghosh, Rina,Maiti, Swaraj B.,Chatterjee, Amareshwar
-
p. 4279 - 4282
(2007/10/02)
-
- Metalation reactions XIII. The reactions of electrophiles with the dilithiated species 1-(α-lithiomethyl)-2-benzene
-
Direct dimetalation of 1-methyl-2-(methylthio)benzene (1) gives the dilithiated species (2) in good yield, which can be used to introduce substituents into the thiomethyl and methyl groups.Species 2 can react also with a variety of dichlorosilanes and dichlorostannanes, and with sulphur chloride, to yield derivatives of 1,3-benzothiasilin, 1,3-benzothiastannin and 1,3-benzodithiin respectively.Reaction of 2 with tetrachlorosilane yields a spirocyclic silicon compound, while reaction with benzoyl chloride yields a derivative of 1-benzothiopyran.
- Cabiddu, S.,Floris, C.,Gelli, G.,Melis, S.
-
-
- The preparation of some thiochroman-3-ones and derivatives
-
The use of 2,3-dihydrobenzothiophene-2,3-dione as a source of 2-mercaptophenylacetic acid permits a convenient preparation of 2-carboxymethylthiophenylacetic acid or derivatives.These undergo a Dieckmann cyclization to 3-acetoxybenzothiopyrans, which m
- Clark, Peter D.,McKinnon, David M.
-
p. 243 - 248
(2007/10/02)
-
- A Synthesis of the 2H-Benzothiocin System through Cycloaddition
-
Thiochroman-3-one has been prepared from o-nitrophenylacetic acid.Cycloaddition of dimethyl acetylenedicarboxylate to the pyrrolidine enamine of thiochroman-3-one, followed by electrocyclic ring opening of the cyclobutene system in the tricyclic adduct, y
- Lamm, Bo,Aurell, Carl-Johan
-
p. 197 - 200
(2007/10/02)
-