Diastereoselective Synthesis of a Highly Functionalized Angularly Substituted cis-Perhydroisoquinoline-3,6-dione via Organoiron

Abstract

Nitrile addition to cyclohexadienyium-Fe(CO)(3) perchlorate salt provides an efficient entry into the angularly substituted cis-fused perhydroisoquinoline ring system. The key steps in the assembly of the angularly substituted cis-octahydroisoquinoline ring are the transformation of the nitrile to an N-(benzylmethylencie)amino group and a diastereoselective intramolecular Michael reaction to form the bicyclic ring.

Tungsten-anisole complex provides 3,6-substituted cyclohexenes for highly diversified chemical libraries

“…Friedel-Crafts-type addition reactions have been observed with other highly electrophilic arene complexes (56), as well as dienyl complexes such as the [Fe(CO) 2 (η 5 -C 6 H 7 )] + system (57). These organometallic complexes have been elaborated into aryl-substituted dienes, enones (52)(53)(54)(55), and carbazoles (58,59). Limited examples of EAS reactions have also appeared in our own work, in the synthesis of γsubstituted enones (60) and tetrahydroindolines ( 61), but before our preliminary report of this study (9), we had been unable to couple these reactions to a second or third nucleophilic addition.…”

“…Regarding other organometallic approaches germane to this study, the manganese system [(η 6 -arene)Mn(CO) 3 ] + can undergo sequential nucleophilic additions to form a cis-5,6,-disubstituted 1,3-cyclohexadiene complex (50). This double nucleophilic addition approach requires highly reactive nucleophiles (e.g., butyllithium), which are not compatible with many other functional groups, and has not been widely applied to organic synthesis (51)(52)(53)(54)(55). Friedel-Crafts-type addition reactions have been observed with other highly electrophilic arene complexes (56), as well as dienyl complexes such as the [Fe(CO) 2 (η 5 -C 6 H 7 )] + system (57).…”

Carbon-Carbon Bond Formation Facilitated by π-Complexed Organometallic Auxiliaries: An Overview

“…Further manipulation of this cyano group produced late-stage intermediate 10 , important in the synthesis of nitraria alkaloids [12]. This method has also been applied to obtain cis -fused perhydroisoquinoline ring systems [13] as well as spiro-oxaquinolizinone (ABC ring) core of upenamide [14].…”