80387-17-3Relevant articles and documents
Titanium-mediated addition of grignard reagents to acyl cyanohydrins: Aminocyclopropane versus 1,4-diketone formation
Setzer, Paul,Forcher, Gwenael,Boeda, Fabien,Pearson-Long, Morwenna S. M.,Bertus, Philippe
, p. 171 - 180 (2014/01/06)
The 1,2-dianion reactivity of the reagent generated from EtMgBr and titanium isopropoxide was illustrated when N-acyl cyanohydrins were used as substrates (>20 examples), giving both aminocyclopropane derivatives and 1,4-dicarbonyl compounds. When the reaction was performed in diethyl ether, 5-hydroxy-1,4-diketones were the main product. Under specific conditions (use of tetrahydrofuran and a bulky carboxylic moiety), the cyclopropane derivatives were obtained in good yields. The observed dichotomy may be explained by a ring-opening of the five-membered titanacycle intermediate followed by a nonselective acyl addition. The 1,2-dianion reactivity of the reagent generated from EtMgBr and Ti(OiPr)4 was illustrated when N-acyl cyanohydrins were used as substrates (>20 examples). When the reaction was performed in diethyl ether, 1,4-diketones were mainly isolated. Under certain conditions, cyclopropane derivatives were also obtained in good yields. A mechanism rationalizing this dichotomy is presented. Copyright
O-Acylation of α-Diazo Ketones. A Novel Route to Alkenediazonium and 1,3-Dioxolium Salts
Lorenz, Wolfgang,Maas, Gerhard
, p. 375 - 381 (2007/10/02)
O-Acylation of α-diazo ketones with benzoyl triflate or diphenylacetyl triflate generates the corresponding β-(acyloxy)alkenediazonium salts 5 and 15.These thermolabile compounds can be trapped with isopropylamine at low temperature to give triazoles 21.Dediazoniation of 5 and 15 leads to 1,3-dioxolium salts 7 and 16 as well as small amounts of vinyl triflates 8 and 17 via intermediary vinyl cations.O-Benzoylation with benzoyl triflate has also been realized for the quinoid α-diazo ketone 9; the resulting diazonium salt 10 gives triazole 13 on treatment with isopropylamine.
