Studies of bioactive heterocycles: amino Claisen rearrangement of 4-N-(4-aryloxybut-2-ynyl),N-methylaminocoumarins
摘要:
Thermal amino-Claisen rearrangement of 4-N-(aryloxybut-2-ynyl), N-methyl-aminocoumarins (8a-e) in refluxing o-dichlorobenzene gave 4-aryloxymethylene-1-methyl-1,2,3-trihydropyrido[3,2-c][1]benzopyran-5-ones (9a-e) in 56-72% isolated yields. Substrates (8a-f) were prepared from 4-chlorocoumarin (6a,b) and N-(4-ary-loxybutynyl),N-methylamine (7a-f) in 68-77% yields. (C) 2001 Elsevier Science Ltd. All rights reserved.
Synthesis of bioactive heterocycles: tandem reaction of 4-N-(4′-aryloxybut-2′-ynyl),N-methylaminocoumarin with 3-chloroperoxybenzoic acid
摘要:
A number of 4-N-(4'-aryloxybut-2'-ynyl).N-methylaminocoumarins (4a-e) on treatment with one equivalent of 3-chloroperoxybenzoic acid at 0-5degreesC for 10 min and then stirring at rt for 10 It afforded pyrrolo[3,2-c]coumarin derivatives in 70-75% yields. The 4-N-(4'-aryloxybut-2'-ynyl),N-methylaminocoumarins 4a-e were in turn prepared from 4-tosyloxycoumarin (2) and (4-arytoxybut-2-ynyl)-N-methylamine (3a-e). (C) 2002 Elsevier Science Ltd. All rights reserved.