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  • Synthetic Approaches to and Structures of Diplatinum Polyynediyl Complexes trans,trans ‐[(C 6 F 5 )(R 3 P) 2 Pt(C≡C) n Pt(PR 3 ) 2 (C 6 F 5 )] With Odd Numbers of Triple Bonds; Avoiding Complicating Ethynediyl Extrusions
Title: Synthetic Approaches to and Structures of Diplatinum Polyynediyl Complexes trans,trans ‐[(C 6 F 5 )(R 3 P) 2 Pt(C≡C) n Pt(PR 3 ) 2 (C 6 F 5 )] With Odd Numbers of Triple Bonds; Avoiding Complicating Ethynediyl Extrusions
Abstract Reactions oftrans‐(C6F5)(p‐tol3P)2Pt(C≡C)nSiEt3(PtC2nSi;n=5, 7, 9) and excessPtClin the presence of wetn‐Bu4N+F−(to effect protodesilylation) under Sonogashira‐type conditions (CuCl, base, other additives) afford the title compoundsPtC10Pt,PtC14Pt, andPtC18Ptin 42–32 % yields. A four‐fold substitution of the phosphine ligands inPtC10Ptby PEt3affordsPt'C10Pt’(78 %), and a Sonogashira reaction ofPt'C2HandPt'ClaffordsPt'C2Pt’(68 %). The analogous reaction withPtC2SiandPtClis unsuccessful, presumably for steric reasons. The crystal structures ofPtC10Pt,PtC14Pt,Pt'C10Pt′, andPt'C2Pt’exhibit a number of interesting trends and features. Certain sp chain extension reactions that lead to or employ the precursorsPtC10Si,PtC12Si,PtC14Si, andPtC18Sisometimes give byproducts derived from C2loss, and possible origins are discussed. Related phenomena have been reported by others in the course of synthesizing extended conjugated polyynes.  more » « less
Award ID(s):
1900549
PAR ID:
10642648
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
European Journal of Inorganic Chemistry
Volume:
27
Issue:
34
ISSN:
1434-1948
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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