Sn(OTf)2 catalysed regioselective styrene oxide ring opening with aromatic amines

Sn(OTf)2 is an efficient and versatile catalyst for the highly regioselective opening of styrene oxide with aromatic amines, which allowed for the preparation of fourteen 2-arylamino-2-phenylethanols, some of them described here for the first time (6g, 6i, 6j, 6k and 6m). Sn(OTf)2 also catalyses the opening of styrene oxide with aliphatic amines in moderate to high yields but with a lower degree of regioselectivity. 2-Akylamino-1-phenylethanols are the predominant products when moderate to high regioselectivity is observed (compounds 4b, 4c and 4d). This is the first report of the use of Sn(OTf)2 to catalyse the opening of an epoxide by aliphatic amines.