Good news! Seems to be a clever approach, possibly a breakthrough. How much will AI boost chemistry?
"Using ozone ... as a reagent and the metal as a catalyst, the scientists were able to break the carbon-carbon bonds of different types of organic molecules. The ozone broke the bonds into hydrocarbons called alkenes, and the copper catalyst coupled the broken bonds with nitrogen, forming carbon-nitrogen bonds, or molecules known as amines.
This process, known as aminodealkenylation, makes good use of an inexpensive metal that is in abundance, as opposed to other similar catalysts that would traditionally be used to develop amines. ..."
"... Traditional metal catalysis uses expensive metals such as platinum, silver, gold and palladium, but the researchers used oxygen and copper — an abundant base metal. ...
One chemical used in some anti-cancer drugs, for example, costs pharmaceutical companies $3,200 per gram — 50 times more than a gram of gold. The UCLA researchers devised an inexpensive way to produce this drug molecule from a chemical costing just $3 per gram. They were also able to apply the process to produce many other chemicals used in medicine and agriculture for a fraction of the usual cost. ..."
From the editor's summary and abstract:
"Editor’s summary
Reactions that form carbon–nitrogen bonds most often target carbon centers that are either single bonded to a halogen or double bonded to oxygen or another carbon. He et al. present an alternative sequence that targets a carbon–carbon single bond adjacent to an olefin. Treatment of the allylic carbon compound with ozone followed by copper catalysis formally displaces the pendant olefin with an amine. The reaction can introduce nitrogen into a wide variety of complex terpenes, among other compounds. ...
Abstract
Great efforts have been directed toward alkene π bond amination. In contrast, analogous functionalization of the adjacent C(sp3)–C(sp2) σ bonds is much rarer. Here we report how ozonolysis and copper catalysis under mild reaction conditions enable alkene C(sp3)–C(sp2) σ bond–rupturing cross-coupling reactions for the construction of new C(sp3)–N bonds. We have used this unconventional transformation for late-stage modification of hormones, pharmaceutical reagents, peptides, and nucleosides. Furthermore, we have coupled abundantly available terpenes and terpenoids with nitrogen nucleophiles to access artificial terpenoid alkaloids and complex chiral amines. In addition, we applied a commodity chemical, α-methylstyrene, as a methylation reagent to prepare methylated nucleosides directly from canonical nucleosides in one synthetic step. Our mechanistic investigation implicates an unusual copper ion pair cooperative process."
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