[EN] PROCESS FOR THE SYNTHESIS OF CYCLIC CARBAMATES<br/>[FR] PROCÉDÉ DE SYNTHÈSE DE CARBAMATES CYCLIQUES
申请人:LONZA AG
公开号:WO2012048884A1
公开(公告)日:2012-04-19
The invention is directed to a process for the preparation of a cyclic carbamate starting with a chiral propargylic alcohol and/or a suitable salt thereof, which is reacted with a cyclisation agent selected from phosgene, diphosgene, triphosgene and mixtures thereof, and in that the reaction is carried out in the presence of an aqueous base, and a water-immiscible organic solvent, said organic solvent mainly comprising at least one compound selected from C2-5-alkyl C2-5-carboxylates and mixtures of at least one C2-5-alkyl C2-5-carboxylate with at least one C5-8-alkane. Another aspect of the invention is directed to a process for the synthesis of said cyclic carbamate starting described above, wherein also a process for the preparation of the chiral propargylic alcohol is provided.
The present invention provides a novel alizarin derivative compound and a simplified and low cost method for preparing an alizarin derivative compound including: obtaining a compound represented by Formula (2) using a compound represented by Formula (3); and obtaining an alizarin derivative compound represented by Formula (1) using the compound represented by Formula (2); in Formulae (1) to (3), R
1
represents a hydrogen atom or a substituent; n represents an integer of 1 to 3, L represents a specific alkyl group; Q represents an atomic group needed to form an aromatic ring or a heteroaromatic ring with adjacent carbon atoms; and P represents an atomic group which includes an atom(s) selected from a hydrogen atom, a carbon atom, an oxygen atom, a sulfur atom, a silicon atom and a boron atom, and which is needed to form a ring structure group with adjacent two oxygen atoms and two carbon atoms;
Practical Catalytic Cleavage of C(sp
<sup>3</sup>
)−C(sp
<sup>3</sup>
) Bonds in Amines
作者:Wu Li、Weiping Liu、David K. Leonard、Jabor Rabeah、Kathrin Junge、Angelika Brückner、Matthias Beller
DOI:10.1002/anie.201903019
日期:2019.7.29
The selective cleavage of thermodynamically stable C(sp3)−C(sp3) single bonds is rare compared to their ubiquitous formation. Herein, we describe a general methodology for such transformations using homogeneous copper‐based catalysts in the presence of air. The utility of this novel methodology is demonstrated for Cα−Cβ bond scission in >70 amines with excellent functional group tolerance. This transformation