Organoiron intermediate

The racemization of optically active halides in the coupling process may, however, also be a result of the configurational lability of organoiron intermediates. 

It seems that transition metal-catalyzed C(sp )-H functionalization is partial to noble palladium catalysts. Virtually, in 2013, Nakamura and coworkers developed a Fe(lll)-catalyzed, 8-aminoquinolinyl auxiliary-assisted P-C(sp )-H arylation with organozinc reagent in the presence of organic halides as oxidant using (Scheme 1.17) [44]. The preliminary mechanistic study suggests an organoiron intermediate 6. In 2014, Gu and Ackerman developed Fe(acac)3-catalyzed... 

When Li-C bonds in di-hthio reagents 1 were transmetallated to Fe-C bonds by use of common and simple FeCls, the in situ generated organoiron intermediates showed different reactivity with that of di-hthio reagents 1. For example, di-hthio reagents 1 did not react with unactivated alkynes such as 4-octyne. However, in the presence... 

The reaction proceeds by an ET pathway giving the I9e organoiron radical cation and the organic radical R which couple in the cage after escape ofX. The cationic Fe1 intermediate is noted at low temperature by its characteristic purple color and the classical spectrum of Fe1 species with rhombic distortion (g = 2.091, 2.012, 2.003 at —140 °C in acetone) before collapse to the orange substituted cyclohexa-dienyl Fe11 complexes. 

The low spin aryliron complexes Fe(Por)Ar behave differently than their alkyl counterparts toward oxygen. In chloroform the products of the reaction of Fe(Por)Ar with O2 are the iron(IV) alkyl Fe(Por)Ar] and Fe(Por)Cl, while in toluene the aryloxide complexes Fe(Por)OAr are formed with no direct evidence for the formation of arylperoxo intermediates."" The high spin iron(lll) alkynyl complexes which have more ionic character in the Fe—C bond do not react with oxygen, and the order of reactivity of organoiron(lll) complexes toward O2 is given by Fe(Por)(alkyl) > Fe(Por)(aryl) > Fe(Por)(C=CR). ... 

Thiapyran derivatives can be prepared from preformed organoiron and -cobalt complexes as in Scheme 160 the organocobalt complex (136) can be used as an intermediate in the synthesis of 1,2-dithia cyclopent-4-en-3-thione (See Scheme 122 in Section IV,H.)... 

Si-Lactams. The synthesis of /5-lactams employing organoiron complexes as intermediates (8, 454-455) has been extended to the preparation of bicyclic lactams, in particular to the new carbopenams. A synthesis of 2-methylcarbopenam (1) is shown in equation (I). 

Cyclizations of alkenic amines and imines using organoiron complexes to generate bicyclic 3-lactams are discussed in Chapter 3.1 of this volume. Examples of heterocyclizations of alkenic NA/-dialkylamine and pyridine derivatives to form cyclic quaternary ammonium salts are cited in the Staninets review.Ic A cyclization of an enol thioether has been used to generate a thiazolidine intermediate used in cephalosporin synthesis (equation 131).262... 

The organosilyl derivative 17 was the exclusive product when 2,3,5-tri-O-benzyl-L-arabinose was treated with phenyldimethylsilylmethyl magnesium chloride, whereas organoiron compound 18 was an intermediate in the synthesis of some hepturonic acid derivatives. Some organomercury compounds were characterized during a study of the stereochemical integrity of the Feirier carbocyclization reaction, and the hexacarbonyldicobalt complexes 19 and 20 have been prepared... 

The chain-extended a,a-trehalose analogue (46) was synthesized via the organoiron(II) intermediate (45) which underwent a carbonyl insertion reaction (Scheme 8). 

---