Facile synthesis ofcyclo-(P₄^tBu₃)-containing oligo- and pnictaphosphanes

Abstract

The cyclo-(P4tBu3) synthon [Li{cyclo-(P4tBu3)}(thf)(tmeda)] (1) (thf = tetrahydrofuran, tmeda = N,N,N′,N′-tetramethylethane-1,2-diamine) is readily accessible in a one-pot synthesis from P4 and LitBu. The use of 1 as a cyclo-(P4tBu3) building block enables the rational...

Coordination chemistry of hepta-tert-butylnonaphosphane

“…We have previously reported an easy and straightforward preparation of { cyclo -(P 4 t Bu 3 )} 2 P t Bu in our studies on activation of white phosphorus (P 4 ) with Li t Bu and the use of Li{ cyclo -(P 4 t Bu 3 )} as a cyclo -(P 4 t Bu 3 ) synthon. 36 Nonaphosphane { cyclo -(P 4 t Bu 3 )} 2 P t Bu 36 ( L ) readily forms complexes with iron(0) ([Fe(CO) 4 L ] ( 1 )), cobalt(− i ) ([Co(CO) 2 (NO) L ] ( 2 )), copper( i ) ([(CuBr) 2 L ] ( 3 )), rhodium( i ) ([RhCl(CO) L ] ( 4 )), and palladium( ii ) ([PdCl 2 L ] ( 5 )) (Scheme 1). Compounds 1–4 were fully characterised by spectroscopic methods and single-crystal X-ray diffraction, while complex 5 was only structurally characterised in the solid state by XRD.…”

“…The most striking features are — apart from considerable line broadening — the rather large 1 J PP coupling J 1,9 / J 5,9 (−321.93(3) Hz) and the 2 J PP coupling J 1,5 (+192.1(2) Hz). The magnitude of the latter is larger than in { cyclo -(P 4 t Bu 3 )} 2 CH 2 (+164.03 Hz), 36 an [A[M] 2 X] 2 spin system,‡‡The most commonly used nomenclature to designate spin systems was first proposed by Pople, Schneider and Bernstein 43 and later extended by Richards and Schaefer. 44 As this nomenclature becomes very cumbersome for complex spin systems, Haigh proposed a more condensed nomenclature, involving the use of square brackets to indicate repeated symmetry-related magnetically non-equivalent groups of nuclei with all nuclei within the square brackets to be magnetically equivalent.…”

“…The most striking features areapart from considerable line broadeningthe rather large 1 J PP coupling J 1,9 /J 5,9 (−321.93(3) Hz) and the 2 J PP coupling J 1,5 (+192.1(2) Hz). The magnitude of the latter is larger than in {cyclo-(P 4 t Bu 3 )} 2 CH 2 (+164.03 Hz), 36 an [A [M] 2 X] 2 spin system, ‡ but comparable to exocyclic 2 J couplings in similar compounds. 40,41 This large magnitude indicates that the respective lone pairs of electrons point towards each other.…”

“…The couplings within the four-membered rings have values which are similar to those of related tert-butyl substituted cyclotetraphosphanes. § 29,36,42 [Co(CO) 2 (NO)({cyclo-(P 4 t Bu 3 )} 2 P t Bu-κP 9 )] (2)…”

Gold(i) complexes of tetra-tert-butylcyclotetraphosphane

“…Bu 3 )} 2 , 18 {cyclo-(P 4 t Bu 3 )} 2 P t Bu, 19 {cyclo-(P 4 t Bu 3 )} 2 CH 2 and E{cyclo-(P 4 t Bu 3 )} 3 (E = As, Sb, and Bi), starting from cyclo-(P 4 t Bu 3 ) synthons, 5,20 and the coordination chemistry of {cyclo-(P 4 t Bu 3 )} 2 18 and its pentalene isomer. The oligodentate ligand {cyclo-(P 4 t Bu 3 )} 2 18 can bind up to three gold(I) chloride fragments.…”