TY - JOUR
T1 - Carbenoid induced irreversible ring opening of naphthopyrans
AU - Gabbutt, Christopher D.
AU - Heron, B. Mark
AU - Thomas, David A.
AU - Light, Mark E.
AU - Hursthouse, Michael B.
PY - 2004/8/2
Y1 - 2004/8/2
N2 - Contrary to expectation rhodium carbenoids do not undergo cycloaddition to the 2H-pyran unit of the isomeric naphthopyrans 3 and 5. With 3, a naphtho[2,1-b]pyran-8-ylacetate, 4 is formed and a novel merocyanine dye 6 results from a cycloaddition across the C-5-C-6 double bond of the naphtho[1,2-b]pyran 5. Tethering the carbenoid to the naphtho[1,2-b]pyran system 5, as in 10, results in a similar mode of addition and affords the intensely coloured tetracycle 11.
AB - Contrary to expectation rhodium carbenoids do not undergo cycloaddition to the 2H-pyran unit of the isomeric naphthopyrans 3 and 5. With 3, a naphtho[2,1-b]pyran-8-ylacetate, 4 is formed and a novel merocyanine dye 6 results from a cycloaddition across the C-5-C-6 double bond of the naphtho[1,2-b]pyran 5. Tethering the carbenoid to the naphtho[1,2-b]pyran system 5, as in 10, results in a similar mode of addition and affords the intensely coloured tetracycle 11.
UR - http://www.scopus.com/inward/record.url?scp=3142730460&partnerID=8YFLogxK
U2 - 10.1016/j.tetlet.2004.06.064
DO - 10.1016/j.tetlet.2004.06.064
M3 - Article
AN - SCOPUS:3142730460
VL - 45
SP - 6151
EP - 6154
JO - Tetrahedron Letters
JF - Tetrahedron Letters
SN - 0040-4039
IS - 32
ER -