Synthesis and Derivatization of the Bis(amido)-lambda(3)-cyclodiphosphazanes cis-[R '(H)NP(mu-NR)](2), Including a Rare Example, trans-[tBu(H)N(Se)P(mu-NCy)](2), Showing Intermolecular Se center dot center dot center dot H-O Hydrogen Bonding

Abstract

The reaction of PCl(3) with CyNH(2) in a 1: 3 ratio afforded the dichloro-lambda(3)-cyclodiphosphazane, cis-[ClP(mu-NCy)](2) (2), whereas the corresponding 1: 5 reaction gave the bis(amido)-lambda(3)- cyclodiphosphazane cis-[Cy(H)NP(mu-NCy)](2) (3) in quantitative yield. The dichloro derivative 2 was converted into 3 by reacting 2 with four equivalents of CyNH(2). The mixed (amido)derivatives cis-[tBu(H)NP(mu-NCy)](2) (4) and cis-[Cy(H)NP(mu-NtBu)](2) (5) were prepared from the reaction of cis-[ClP(mu-NCy)](2) (2) and cis-[ClP(mu-NtBu)](2) (1a) with a four-fold excess of the respective primary amines. The oxidation of the bis(amido)-lambda(3)-cyclodiphosphazanes 3-5 with two equivalents of H(2)O(2)/H(2)O, S(8), and Se(8) produced the bis(oxo) [R'(H)N(O)P(mu-NR)](2) [R = R' = Cy (6); R = tBu, R' = Cy (7); R = Cy, R' = tBu (8)], bis(sulfide) [R'(H)N(S)P(mu-NR)](2) [R = R' = Cy (9); R = tBu, R' = Cy (10); R = Cy, R' = tBu (11)], and bis(selenide) [R'(H)N(Se)P(mu-NR)](2) [R = R' = Cy (12); R = tBu, R' = Cy (13); R = Cy, R' = tBu (14)] derivatives, respectively. The reaction of cis-[R(H)NP(mu-NtBu)](2) with two equivalents of phosphoryl azide, [N(3)P(O)(OPh)(2)], afforded the corresponding bis( iminophosphoryl) derivatives, cis-{R(H) N[(OPh)(2)-P( O)N]P(mu-NtBu)}(2) [R = tBu (15), R = Ph (16), R = Cy (17)]. The solid-state structures for 11, 12, 13, and 15 were determined by single-crystal X-ray diffraction studies. Interestingly, the bis(selenide) derivative [tBu(H)N(Se) P(mu-NCy)](2) 13 turned out be a trans isomer in the solid state, whereas the other cyclodiphosphazane derivatives exhibited the cis geometry. Compounds 13 and 15 crystallized along with a water molecule that facilitated the intermolecular Se center dot center dot center dot H-O and N center dot center dot center dot H-O hydrogen bonding, respectively, to form a linear 1D hydrogen bonding network.