Synthesis, Solution, and Structural Characterization of Tetrahydrofuranyl-2,2-Bisphosphonic Acid Disodium Salt

Table 4

Selected bond lengths for Na⁺ and Ca²⁺ bisphosphonate complexes. The L, L1, L2, L3 bisphosphonates are according to Scheme 2.

Compound	Charge of bisphosphonate anion	M–Ohydroxy/furanyl/Å	Shortest M–Ophosporyl/Å	Longest M–Ophosporyl/Å	References
Na2H2L	(−2)	2.79 (1)	2.327 (7)	2.873 (8)	This work
CaH2L1	(−2)	2.608 (2)	2.352 (1)	2.608 (2)	[16]
NaH3L1	(−1)	2.470 (4)	2.230 (4)	2.447 (4)	[17]
NaH3L1	(−1)	2.463 (2)	2.293 (3)	2.444 (2)	[18]
CaH2L2	(−2)	a	2.288 (1)	2.387 (1)	[19]
Na2H2L2	(−2)	2.828 (3)	2.274 (3)	2.691 (3)	[20]
NaH3L2	(−1)	2.537 (2)	2.261 (2)	2.438 (2)	[21]
CaH2L3	(−2)	a	2.304 (1)	2.345 (1)	[22]

a Non bonding distance above 3 Ǻ.