Search for "[5 1] annulation" in Full Text gives 3 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196
Beilstein J. Org. Chem. 2016, 12, 2204–2210, doi:10.3762/bjoc.12.211
Beilstein J. Org. Chem. 2007, 3, No. 11, doi:10.1186/1860-5397-3-11