281195-09-3Relevant academic research and scientific papers
A versatile approach to noncoded β-hydroxy-α-amino esters and α-amino acids/esters from morita-baylis-hillman adducts
Ullah, Hamid,Ferreira, Andr V.,Bendassolli, Jos A.,Rodrigues, Manoel T.,Formiga, Andr Luiz B.,Coelho, Fernando
, p. 113 - 123 (2015/02/02)
A simple and straightforward approach to the diastereoselective synthesis of noncoded β-hydroxy-α-amino esters from Morita-Baylis-Hillman (MBH) adducts is described. The strategy is based on a one-pot sequence involving an oxidative cleavage of the double bond of silylated Morita-Baylis-Hillman adducts, followed by the reaction with hydroxylamine hydrochloride/pyridine to form oximes. The stereoselective reduction of the oximes with the mixture MoCl5·nH2O/NaBH3CN led to the corresponding anti-β-hydroxy-α-amino esters in four steps in good overall yield and with diastereoselectivity higher than 95%. A slight modification of the synthetic approach has allowed for the racemic synthesis of a set of noncoded α-amino esters/acids and DOPA
Heterocycles from Morita-Baylis-Hillman adducts: Synthesis of 5-oxopyrazolidines, arylidene-5-oxopyrazolidines, and oxo-2,5-dihydro-pyrazols
Correia, José Tiago M.,Rodrigues Jr., Manoel T.,Santos, Hugo,Tormena, Cláudio F.,Coelho, Fernando
, p. 826 - 832 (2013/07/25)
Starting from Morita-Baylis-Hillman (MBH) adducts, an approach for the synthesis of oxopyrazolidines, arylidene-oxopyrazolidines, and oxo-2,5-dihydropyrazoles is described. The method is based on a tandem process involving a Michael addition of amino-guan
Hyphenating the curtius rearrangement with morita-baylis-hillman adducts: Synthesis of biologically active acyloins and vicinal aminoalcohols
Amarante, Giovanni W.,Cavallaro, Mayra,Coelho, Fernando
experimental part, p. 1568 - 1584 (2011/11/06)
Using Morita-Baylis-Hillman adducts as substrates, the Curtius rearrangement was performed in a sequence that allowed the synthesis of several hydroxy-ketones (acyloins) with great structural diversity and in good overall yields. These acyloins in turn were easily transformed into 1,2-anti aminoalcohols through a highly diastereoselective reductive amination step. The synthetic utility of these approaches was exemplified by performing the syntheses of (±)-bupropion, a drug used to treat the abstinence syndrome of smoker and (±)-spisulosine, a potent anti-tumoral compound originally isolated form a marine source.
Acyloins from Morita-Baylis-Hillman adducts: an alternative approach to the racemic total synthesis of bupropion
Amarante, Giovanni W.,Rezende, Patrícia,Cavallaro, Mayra,Coelho, Fernando
, p. 3744 - 3748 (2008/09/21)
In this Letter, we describe an easy and straightforward strategy for the preparation of acyloins (α-hydroxyketones) from Morita-Baylis-Hillman adducts, based on a Curtius rearrangement. Different acyloins were obtained with good overall yield (>40% for three steps). To exemplify the synthetic usefulness of this strategy, total synthesis of (±)-bupropion, a dopamine, and nor-epinefrine reuptake inhibitor has been accomplished in eight steps with an overall yield of 25%.
Ozonolysis of Morita-Baylis-Hillman adducts originated from aromatic aldehydes: an expeditious diastereoselective approach for the preparation of α,β-dihydroxy-esters
Abella, Carlos A.M.,Rezende, Patrícia,Lino de Souza, Michele F.,Coelho, Fernando
, p. 145 - 148 (2008/04/13)
We disclose herein ozonolysis of Morita-Baylis-Hillman adducts originated from aromatic aldehydes. This efficient reaction provides α-ketoesters with different substitution patterns on the aromatic ring. Diastereoselective reduction of the corresponding α-ketoester obtained in the oxidative cleavage step provides α,β-dihydroxy-esters with excellent degree of anti diastereoselection. The method is simple and easy to execute and is therefore a valuable alternative to prepare either α-ketoesters or α,β-dihydroxy-esters.
Diastereoselective epoxidation of allylic diols derived from Baylis-Hillman adducts
Porto, Ricardo S.,Vasconcellos, Mario L. A. A.,Ventura, Elizete,Coelho, Fernando
, p. 2297 - 2306 (2007/10/03)
The results of a highly diastereoselective epoxidation of allylic diols derived from Baylis-Hillman adducts are reported. The formation of an intramolecular hydrogen bond seems to be responsible for the high anti diastereoselection obtained in this epoxid
An easy conversion of the Baylis-Hillman adducts into tert- butyldimethylsilyl ethers with tert-butyldimethylsilyl chloride and Li 2S
Mamaghani, Manouchehr,Badrian, Abed
, p. 2429 - 2435 (2007/10/03)
The hydroxy group of the Baylis-Hillman adducts is protected with the t-butyldimethylsilyl (TBDMS) group using the reaction of adducts 1a-h with tert-butyldimethylsilyl chloride (TBDMSCl) in the presence of lithium sulfide under nearly acidic reaction con
Diastereoselective heterogeneous catalytic hydrogenation of Baylis- Hillman adducts
Mateus, Cristiano R.,Almeida, Wanda P.,Coelho, Fernando
, p. 2533 - 2536 (2007/10/03)
We describe herein our results concerning a highly diastereoselective heterogeneous hydrogenation of Baylis-Hillman adducts obtained from aromatic aldehydes. The results obtained are complementary to those already described for homogeneous catalytic hydro
