Asymmetric hydrogenation reactions mediated by a new class of bicyclic bisphosphinites

Autor:	Mark J. Burk, Stanley M. Roberts, Nadine Derrien, Cyril B. Dousson, Ulrich Berens, Manuela Ohff
Rok vydání:	1999
Předmět:	Bicyclic molecule Stereochemistry Organic Chemistry Asymmetric hydrogenation Diol chemistry.chemical_element Alcohol Medicinal chemistry Catalysis Rhodium Inorganic Chemistry chemistry.chemical_compound chemistry Yield (chemistry) Physical and Theoretical Chemistry
Zdroj:	Tetrahedron: Asymmetry. 10:3341-3352
ISSN:	0957-4166
DOI:	10.1016/s0957-4166(99)00341-9
Popis:	The bicyclic alcohol (−)- 4 was prepared from (−)-bicyclo[3.2.0]hept-2-en-6-one (−)- 1 in 50% yield. The diol (−)- 4 was coupled to selected chlorophosphines 6 – 12 to produce a series of bisphosphinites 13 – 19 in 89–95% yield. From these bisphosphinites were prepared the rhodium complexes 20 – 26 which were characterised by 31 P NMR and used in situ for the asymmetric hydrogenation of α-enamides 27 – 29 . Complexes 21 , 23 – 25 proved to be the superior catalysts for the production of ( R )- N -acetylphenylalanine (91, 84, 90 and 87.5% ee) from 27 and ( S )- N -acetylalanine methyl ester (70, 72, 68 and 71% ee) from 28 .
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::7d2f12b4b49720b440ed0c942213a2d5 https://doi.org/10.1016/s0957-4166(99)00341-9 Zobrazit plný text záznamu Full Text from ScienceDirect