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1.
Proc Natl Acad Sci U S A ; 110(27): 10904-9, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23784777

RESUMO

The identification of synthesizable substructural domains within more complex structural targets is of significant value in designing a workable plan of synthesis. We term this process "pattern recognition analysis" (PRA). In this paper we continued to build on the theme of PRA as a potential resource in retrosynthetic blueprints to reach highly challenging targets. The paper operates at two levels. First, there is provided a clear sense of definitions of categories by which patterns are related to hypothetical reaction types. Although the required reaction type may for the moment not exist, we believe that this method of analysis is likely to promote innovation that identifies unmet needs and opportunities to advance the cause of complex target synthesis. In addition, we describe reductions to practice in expanding the menu of achievable patterns. It is likely that the future value of PRA will be associated with its utility in leading the way to new and exploitable chemical innovation.


Assuntos
Técnicas de Química Sintética/métodos , Reação de Cicloadição/métodos , Estrutura Molecular , Estereoisomerismo
2.
Chem Commun (Camb) ; 48(10): 1496-8, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21984365

RESUMO

Ketones react with allyl acetate to generate tertiary homoallylic alcohols in the presence of a rhodium catalyst and bis(pinacolato)diboron. A range of substrates, including aryl, alkyl and cyclic ketones react smoothly under these conditions. Diastereoselective allylation reactions of functionalized ketones such as pregnenolone acetate are also reported.


Assuntos
Cetonas/química , Compostos Organometálicos/química , Propanóis/síntese química , Ródio/química , Acetatos/química , Alquilação , Compostos Alílicos/química , Catálise , Estrutura Molecular , Oxirredução , Propanóis/química , Estereoisomerismo
3.
Org Lett ; 13(19): 5188-91, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21866944

RESUMO

Complementary stereospecific and stereoconvergent reactions for enantioselective synthesis of 1,3-oxazolidines are reported. In the presence of a rhodium catalyst, reaction of enantioenriched butadiene monoxide with aryl imines is stereospecific (99% ee). Alternatively, the reaction of racemic butadiene monoxide, in the presence of a chiral palladium or nickel catalyst, provides an enantioselective synthesis of 1,3-oxazolidines (up to 94% ee). Synthesis of either the cis- or trans-1,3-oxazolidines is also accomplished under catalyst control.


Assuntos
Oxazóis/síntese química , Catálise , Cinética , Estrutura Molecular , Estereoisomerismo
4.
Tetrahedron Lett ; 52(31): 3957-3959, 2011 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-21808427

RESUMO

Reductive alkylation of Diels-Alder derived ring junction- α-cyanoketones provides a route to trans-fused bicyclic systems.

5.
Org Lett ; 11(2): 485-8, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19093851

RESUMO

An allylation reaction that generates homoallylic amines using allyl trifluoroacetate as a nucleophilic allylmetal precursor is reported. A palladium complex catalyzes two transformations in one pot: formation of allylsilane from allyl trifluoroacetate using hexamethyldisilane and subsequent imine allylation. A three-component reaction was developed where preformed imines were replaced with aldehydes and anisidine. Under these reaction conditions a variety of substrates, including electron-rich aromatic and aliphatic aldehydes, react smoothly to afford homoallylic amines.

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