Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
|
Unless otherwise noted, the [2+2] cycloaddition conditions were the same as in Table 1, entry 8; and the synthesis of product 4 followed the same procedure as in Table 2, entry 5. Isolated yields of 3 and 4 are based on 1. The ee value was determined by HPLC on a chiral stationary phase.
Cu(OTf)2 (10 mol%).
Cu(OTf)2 (7.5 mol%).
4fa : 3fa = 19 : 1.
4la : 3la = 9 : 1.
Cu(OTf)2 (12.5 mol%).
