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Title: The synthesis of PNP-supported low-spin nitro manganese(I) carbonyl complexes

Abstract

In this study, the coordination chemistry of Mn(CO) 5Br was investigated with a series of PNP-pincer ligands. The ligands iPrPONOP ( iPrPONOP = 2,6-bis(diisopropylphosphinito)pyridine) and iPrPN HP ( iPrPN HP = HN{CH 2CH 2(PiPr 2)} 2) gave the desired organometallic manganese complexes ( iPrPONOP)Mn(CO) 2Br and ( iPrPN HP)Mn(CO) 2Br, respectively, upon chelation to Mn(CO) 5Br. The reactivity of iPrPNNNP ( iPrPNNNP = N,N'-bis(diisopropylphosphino)-2,6-diaminopyridine) with Mn(CO) 5Br yielded a pair of products, [( iPrPNNNP)Mn(CO) 3][Br] and ( iPrPNNNCO)Mn(CO) 3. The formation of the asymmetric chelate arises from a formal loss of iPr 2PBr and C–N bond formation from a carbonyl ligand and NH, yielding a Mn(I) amide core. The nitration reactions of ( iPrPONOP)Mn(CO) 2Br and ( iPrPN HP)Mn(CO) 2Br were carried out using silver nitrite, yielding the nitro compounds ( iPrPONOP)Mn(CO) 2(NO 2) and ( iPrPN HP)Mn(CO) 2(NO 2), respectively. The analogous iron complex ( iPrPONOP)Fe(CO)Cl 2 was nitrated under the same conditions to yield the salt pair [( iPrPONOP)Fe(CO) 2][FeCl 3NO]. This reactivity underlines the difference between iso-valent iron and manganese centers. The manganese complexes ( iPrPONOP)Mn(CO) 2(NO 2) and ( iPrPN HP)Mn(CO) 2(NO 2) were ineffective as oxygen atom transfer reagents for a variety of substrates.

Authors:
 [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1255273
Report Number(s):
LA-UR-16-20260
Journal ID: ISSN 0277-5387
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Polyhedron
Additional Journal Information:
Journal Name: Polyhedron; Journal ID: ISSN 0277-5387
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Tondreau, Aaron M., and Boncella, James M.. The synthesis of PNP-supported low-spin nitro manganese(I) carbonyl complexes. United States: N. p., 2016. Web. doi:10.1016/j.poly.2016.04.007.
Tondreau, Aaron M., & Boncella, James M.. The synthesis of PNP-supported low-spin nitro manganese(I) carbonyl complexes. United States. doi:10.1016/j.poly.2016.04.007.
Tondreau, Aaron M., and Boncella, James M.. 2016. "The synthesis of PNP-supported low-spin nitro manganese(I) carbonyl complexes". United States. doi:10.1016/j.poly.2016.04.007. https://www.osti.gov/servlets/purl/1255273.
@article{osti_1255273,
title = {The synthesis of PNP-supported low-spin nitro manganese(I) carbonyl complexes},
author = {Tondreau, Aaron M. and Boncella, James M.},
abstractNote = {In this study, the coordination chemistry of Mn(CO)5Br was investigated with a series of PNP-pincer ligands. The ligands iPrPONOP (iPrPONOP = 2,6-bis(diisopropylphosphinito)pyridine) and iPrPNHP (iPrPNHP = HN{CH2CH2(PiPr2)}2) gave the desired organometallic manganese complexes (iPrPONOP)Mn(CO)2Br and (iPrPNHP)Mn(CO)2Br, respectively, upon chelation to Mn(CO)5Br. The reactivity of iPrPNNNP (iPrPNNNP = N,N'-bis(diisopropylphosphino)-2,6-diaminopyridine) with Mn(CO)5Br yielded a pair of products, [(iPrPNNNP)Mn(CO)3][Br] and (iPrPNNNCO)Mn(CO)3. The formation of the asymmetric chelate arises from a formal loss of iPr2PBr and C–N bond formation from a carbonyl ligand and NH, yielding a Mn(I) amide core. The nitration reactions of (iPrPONOP)Mn(CO)2Br and (iPrPNHP)Mn(CO)2Br were carried out using silver nitrite, yielding the nitro compounds (iPrPONOP)Mn(CO)2(NO2) and (iPrPNHP)Mn(CO)2(NO2), respectively. The analogous iron complex (iPrPONOP)Fe(CO)Cl2 was nitrated under the same conditions to yield the salt pair [(iPrPONOP)Fe(CO)2][FeCl3NO]. This reactivity underlines the difference between iso-valent iron and manganese centers. The manganese complexes (iPrPONOP)Mn(CO)2(NO2) and (iPrPNHP)Mn(CO)2(NO2) were ineffective as oxygen atom transfer reagents for a variety of substrates.},
doi = {10.1016/j.poly.2016.04.007},
journal = {Polyhedron},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 9
}

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