Nitridomanganese chiral

Scheme 13. Synthesis of chiral nitridomanganese complex using liquid NH3/NBS system.

An alternative procedure to afford the chiral nitridomanganese complex 15 was developed by our group. This procedure consists of a reaction of the chiral Mnra complex 14 [21] with gaseous NH3 and chloramine-T as the oxidant in MeOH [22] (Scheme 15). Other derivatives 16-21 which have (1 / ,2/ )-diaminocyclohex-ane as a backbone were synthesized by the usual method using aqueous NH3 and NaOCl. Complex 22 was also synthesized from diphenylethylenediamine as a chiral source (Scheme 16). 

Asymmetric Aziridination of Olefins with Chiral Nitridomanganese Complexes... 

Scheme 23. Asymmetric aziridination of 1-vinylcyclohex-l-ene with chiral nitridomanganese complexes.

The chiral nitridomanganese complex 545 represents a novel self-contained asymmetric nitrogen-transfer reagent which has been used to convert alkenes to scalemic aziridines directly, although a stoichiometric amount of transfer reagent is required. This protocol makes use of A -2-(trimethylsilyl)ethanesulfonyl chloride (SESCl) (546) as an activator, providing A -SES-aziridines 547 that are easily deprotected under mild conditions using... 

Nitridomanganese Complexes. Stoichiometric amounts of chiral complexes of type 43 react with silyl enol ethers in the presence of trifluoroacetic or /Moluenesulfonic anhydride to give a-(A-trifluroacetyl)amino- and a-(N-p-tosylamino) ketones, respectively (see Eq. 160).350 - 353 With glycals, the 1-hydroxy-2-( A -trifluoroacetyljamino derivatives are formed (see Eq. 83).354 A mechanism involving approach of the enol ether from the least hindered side of the 43-TFA complex has been proposed.353... 

Some new methods have been developed to synthesise oxazolines. Using the chiral nitridomanganese complex 154 (stoichiometric) in the presence of acyl chlorides, it was possible to obtain oxazolines from alkenes. The reaction afforded enantioenriched oxazolines in good yield and selectivity mainly using ( ) olefins <01TL9019>. 

Synthesis of chiral SES aziridines was also performed by using a chiral nitridomanganese complex activated by silver salt and SES-Cl (3) (eq 26 and Table 6). Like that for the sulfonyl-iminoiodinane process, this reaction proceeds via nitrogen atom... 

Nitridomanganese complex was first applied to asymmetric aziridination reactions of alkenes by Komatsu and coworkers in 1998 [9]. The reaction of styrene with the chiral nitridomanganese 3 [10] in the presence of pyridine, TS2O,... 

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