Low catalyst loadings in olefin metathesis: synthesis of nitrogen heterocycles by ring-closing metathesis.
نویسندگان
چکیده
A series of ruthenium catalysts have been screened under ring-closing metathesis (RCM) conditions to produce five-, six-, and seven-membered carbamate-protected cyclic amines. Many of these catalysts demonstrated excellent RCM activity and yields with as low as 500 ppm catalyst loadings. RCM of the five-membered carbamate series could be run neat, the six-membered carbamate series could be run at 1.0 M, and the seven-membered carbamate series worked best at 0.2-0.05 M.
منابع مشابه
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ورودعنوان ژورنال:
- Organic letters
دوره 12 5 شماره
صفحات -
تاریخ انتشار 2010