The first example of oxidant-free cobalt-catalyzed synthesis of five-membered spirocycles is reported from benzimidates and maleimides utilizing nitrobenzene as promoter. In contrast to previously known cobalt-catalyzed oxidative C–H functionalization reactions, this transformation occurs efficiently in the absence of oxidant and is accompanied by liberation of hydrogen. The spiro-lactams were readily
Overcoming the Limitations of C−H Activation with Strongly Coordinating N-Heterocycles by Cobalt Catalysis
作者:Hui Wang、Mélanie M. Lorion、Lutz Ackermann
DOI:10.1002/anie.201603260
日期:2016.8.22
Stronglycoordinating nitrogen heterocycles, including pyrimidines, oxazolines, pyrazoles, and pyridines, were fully tolerated in cobalt‐catalyzed C−H amidations by imidate assistance. Structurally complex quinazolines are thus accessible in a step‐economic manner. Our findings also establish the relative powers of directing groups in cobalt(III)‐catalyzed C−H functionalization for the first time.
Manganese-Catalyzed <i>ortho</i>
-C−H Alkenylation of Aromatic N−H Imidates with Alkynes: Versatile Access to <i>Mono</i>
-Alkenylated Aromatic Nitriles
作者:Xiaoxu Yang、Xiqing Jin、Congyang Wang
DOI:10.1002/adsc.201600128
日期:2016.7.28
So far, the direct C−H alkenylation of aromatic nitriles with alkynes has not been achieved. Herein, we discribe the first manganese‐catalyzed C−H alkenylation of aromatic N−H imidates to access mono‐alkenylated aromatic nitriles. The reaction is accelerated by the presence of a catalytic amount of sodium pivalate. This protocol is also highlighted by the simple catalytic system, good compatibility
Solid-phase synthesis of 1-substituted 4,5-dihydro-1,2,4-triazin-6-ones
作者:Blanca Martı́nez-Teipel、Enrique Michelotti、Martha J Kelly、Damian G Weaver、Francis Acholla、Kebede Beshah、Jordi Teixidó
DOI:10.1016/s0040-4039(01)01095-4
日期:2001.9
The solid-phase synthesis of 1-substituted 4,5-dihydro-1,2,4-triazin-6-ones from imidate esters and substituted hydrazines is reported. The synthesis starts with the reaction of imidic esters with polymer-bound glycine to form the imidate esters. A rehearsal library of 59 compounds was synthesized.
Novel compounds of the general formula:
1
and pharmaceutically acceptable acid addition salts thereof, wherein the compounds are useful in therapy to protect skeletal muscles against damage resulting from trauma or to protect skeletal muscles subsequent to muscle or systemic diseases such as intermittent claudication, to treat shock conditions, to preserve donor tissue and organs used in transplants, in the treatment of diabetes, in the treatment of cardiovascular diseases including atrial and ventricular arrhythmias, Prinzmetal's (variant) angina, stable angina, and exercise induced angina, congestive heart disease, and myocardial infarction.