In:
Applied Organometallic Chemistry, Wiley, Vol. 34, No. 3 ( 2020-03)
Abstract:
A series of phosphorus‐chalcogen chelated hydrido iron (II) complexes 1–7 , ( o ‐(R' 2 P)‐ p ‐R‐C 6 H 4 Y)FeH (PMe 3 ) 3 ( 1 : R = H, R' = Ph, Y = O; 2 : R = Me, R' = Ph, Y = O; 3 : R = H, R' = i Pr, Y = O; 4 : R = Me, R' = i Pr, Y = O; 5 : R = H, R' = Ph, Y = S; 6 : R = Me, R' = Ph, Y = S; 7 : R = H, R' = Ph, Y = Se), were synthesized. The catalytic performances of 1–7 for dehydration of amides to nitriles were explored by comparing three factors: (1) different chalcogen coordination atoms Y; (2) R' group of the phosphine moiety; (3) R substituent group at the phenyl ring. It is confirmed that 5 with S as coordination atom has the best catalytic activity and 7 with Se as coordination atom has the poorest catalytic activity among complexes 1 , 5 and 7 . Electron‐rich complex 4 is the best catalyst among the seven complexes and the dehydration reaction was completed by using 2 mol% catalyst loading at 60 °C with 24 hr in the presence of (EtO) 3 SiH in THF. Catalyst 4 has good tolerance to many functional groups. Among the seven iron complexes, new complexes 3 and 4 were obtained via the O‐H bond activation of the preligands o ‐ i Pr 2 P(C 6 H 4 )OH and o ‐ i Pr 2 P‐ p ‐Me‐(C 6 H 4 )OH by Fe(PMe 3 ) 4 . Both 3 and 4 were characterized by spectroscopic methods and X‐ray diffraction analysis. The catalytic mechanism was experimentally studied and also proposed.
Type of Medium:
Online Resource
ISSN:
0268-2605
,
1099-0739
Language:
English
Publisher:
Wiley
Publication Date:
2020
detail.hit.zdb_id:
1480791-9
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