Journal of the Chemical Society. Perkin Transactions 2 (2001) p. 1081 - 1093 (1996)
Update date:2022-08-04
Topics:
Ali, Amjad
Bryon Gill
Pattenden, Gerald
Roan, Graeme A.
Kam, Toh-Seok
Cobalt(i)-mediated mono- and bi-cyclisations of halo-polyenes are compared and contrasted with corresponding reactions using the Heck reaction. The procedures are found to complement one another, with each having advantages and disadvantages, in the cases studied. Thus, treatment of the vinyl iodide 1 under Heck conditions led to the novel 1,3-diene 3 in 93% yield, whereas reaction between 1 and cobalt(I) salophen resulted in the formation of the organocobalt complex 4 ( ～ 50%) as black crystals. Subsequent irradiation of 4 then led to the 6,5-ring fused bicycle 5 in 85% yield. In similar fashion, a Heck reaction with the analogous vinyl iodide 8 produced the product 9 of 6-ring cyclisation followed by β-hydride elimination, whereas the corresponding cobalt-mediated reaction with 8 led to the new organocobalt 10 albeit in only low yield ( ～ 20%). In reactions akin to those studied by Overman et al., Heck reaction with the dienyl aryl iodide 14 was shown to lead to a mixture of the bicycle 16 and the tricycle 17 in a 1:1 ratio. By contrast treatment of 14 with cobalt(I) salophen produced largely the tetralin 18. The iodo-diene 33 gave rise to the spirocycle 35 under Heck reaction conditions, and the related spirocycle 42 was produced from the bromo-acetal 40 via 41, using cobalt(I) mediated reactions.
View MoreReliable Pharma Technology (Shanghai) Co., Ltd.
Contact:0086-21-67676847-8008
Address:Lane 1500, No.68, Xinfei Road, Songjiang District, Shanghai, 201611, P.R.China.
Chengdu Gelipu Biotechnology Co., Ltd.
website:http://www.glp-china.com
Contact:86-28-82610909
Address:chegndu
Zibo Ocean International Trade Co.,Ltd(expird)
Contact:+86 533 5160706
Address:1117, Hongtai Bld., Songling rd, Zichuan,Zibo,Shandong,China
Changzhou Sunsheng Chem Co., Ltd
Contact:+1-(989)-854-0648
Address:No. 28 Yinshan Rd., Xixiashu Industrial Park
Contact:0027-717-456976
Address:2ND FLOOR, 325 VAUSE ROAD, OVERPORT, 4001, SOUTH AFRICA
Doi:10.1039/jr9380000172
(1938)Doi:10.1002/ardp.19422800602
(1942)Doi:10.1139/v65-004
(1965)Doi:10.1055/s-0033-1339550
(2013)Doi:10.1021/acs.orglett.0c02408
(2020)Doi:10.1021/ja01608a061
(1955)
