Functionalization of 3‐Iodo‐N,N‐Diisopropylferrocene‐Carboxamide, a Pivotal Substrate to Open the Chemical Space to 1,3‐Disubstituted Ferrocenes

Abstract

No Abstract

O‐Isopropylferrocenesulfonate: Synthesis of Polysubstituted Derivatives and Electrochemical Study

“…Since our preliminary results in the ferrocene series using dialkylcarboxamides as directing groups (DG), [20,22] we have disclosed more appropriate substituents (fluorine, [23] chlorine [23a] and dialkylsulfonamides [14] ) to direct "halogen dance" by exerting acidifying and/or coordinating effect(s) that stabilize the lithio product. These substituents are efficient when combined with a protecting group (PG) that avoids competitive deprotometalation at the otherwise free position next to the DG.…”

On the N‐Arylation of Acetamide Using 2‐, 3‐ and 1’‐Substituted Iodoferrocenes**

“…Dioxane was distilled over CaH 2 . Iodoferrocene ( 1 a ), [17,37] 2‐iodoferrocenecarboxylic acid, [17] 1‐iodo‐3/1’‐methylferrocenes ( 3 b [19i] and 5 b [19j] ), 1‐(diisopropylaminomethyl)‐3/1’‐iodoferrocenes ( 3 c [19a] and 5 c [19j] ), 1‐iodo‐3/1’‐(methoxymethyl)ferrocenes ( 3 d [19i] and 5 d [19j] ), 3/1’‐iodoferrocenemethanols ( 3 e [19i] and 5 e [19j] ), 3/1’‐iodoferrocenecarboxaldehydes ( 3 f [19i] and 5 f [19j] ), (3/1’‐iodoferrocenyl)phenylketones ( 3 g [19i] and 5 g [19j] ), 2/3/1’‐iodoferrocenecarbonitriles ( 1 h , [20] 3 h [19i] and 5 h [19j] ), methyl 3/1’‐iodoferrocenecarboxylates ( 3 i [19i] and 5 i [19j] ), 2/3/1’‐iodo‐ N , N ‐diisopropylferrocenecarboxamides ( 1 j , [19a] 3 j [19a] and 5 j [19j] ), 2/3/1’‐iodo‐ N , N ‐dimethylferrocenamines ( 1 k , [21] 3 k , [19i] and 5 k [19j] ), N ‐( tert ‐butoxycarbonyl)‐3/1’‐iodoferroceneamines ( 3 l [19i] and 5 l [19j] ), and 1‐fluoro‐2/3‐iodoferrocenes ( 1 m [19c] and 3 m [19g] ) were prepared as described previously.…”

“…1‐Azidocarbonyl‐2‐iodoferrocene (racemic mixture) was prepared by adapting a reported procedure [19i] . Triethylamine (2.8 mL, 20 mmol) was added to a solution of 2‐iodoferrocenecarboxylic acid (1.4 g, 4.0 mmol) in dichloromethane (5 mL) at 40 °C.…”

“…1‐(tert‐Butoxycarbonylamino)‐2‐iodoferrocene ( 1 l , racemic mixture) was prepared by adapting a reported procedure [19i] . tert ‐Butanol (1.35 mL, 14 mmol) was added to a solution of 1‐azidocarbonyl‐2‐iodoferrocene (1.0 g, 2.8 mmol) in toluene (23 mL) at room temperature and the reaction mixture was heated at 110 °C for 1 h. The reaction mixture was cooled to room temperature and volatiles were removed under reduced pressure.…”

Remote Deprotometalation-Iodolysis of N,N-Diisopropyl-2-trimethylsilylferrocenecarboxamide: A New Route Toward 1,1′-Disubstituted Ferrocenes

“…While the borane-mediated reduction of similar substrates is well known, 25,30 transformation of the resulting diisopropylamine moiety did not receive much attention 31 until we recently documented the substitution of this bulky amine for an acetate. 32 Consequently, the carboxamide 4 was reduced by an excess of borane (generated in situ from sodium borohydride and iodine) in refluxing tetrahydrofuran to deliver 5 in a 95% yield (Scheme 3). The substitution step then occurred smoothly in neat acetic anhydride at 160 °C for 1 hour and 6 was isolated in a 88% yield on a 20 mmol scale (6.7 g of compound in a single batch).…”