Table 2.
Important IR spectral data (cm−1) of Schiff bases and their corresponding organotin(IV) complexes.
| Compounds | ν(OH)ν | ν(C=N–) | ν(C=O) | ν as(COO) | ν s(COO) | Δν | ν(Sn←N) | ν(Sn–O) | ν(Sn–C) |
|---|---|---|---|---|---|---|---|---|---|
| L1H | 3090–2740 br | 1620 s | 1728 s | — | — | — | — | — | — |
| Bu2Sn(L1)2 | — | 1610 s | 1722 s | 1590 vs | 1325 s | 265 | 540 w | 430 m | 622 m |
| L2H | 3100–2740 br | 1625 s | 1730 s | — | — | — | — | — | — |
| Bu2Sn(L2)2 | — | 1612 s | 1726 s | 1605 m | 1333 m | 272 | 545 m | 426 s | 640 m |
| L3H | 3090–2750 br | 1630 s | 1720 s | — | — | — | — | — | — |
| Bu2Sn(L3)2 | — | 1616 s | 1722 s | 1601 s | 1332 m | 268 | 552 m | 425 m | 630 m |
| L4H | 3110–2750 br | 1622 s | 1735 s | — | — | — | — | — | — |
| Bu2Sn(L4)2 | — | 1605 s | 1732 s | 1608 s | 1330 m | 278 | 545 s | 420 w | 635 m |
| L5H | 3080–2730 br | 1630 s | 1735 s | — | — | — | — | — | — |
| Bu2Sn(L5)2 | — | 1612 s | 1734 s | 1595 vs | 1326 s | 269 | 540 w | 425 w | 625 m |
| L6H | 3109–2730 br | 1622 s | 1725 s | — | — | — | — | — | — |
| Bu2Sn(L6)2 | — | 1610 s | 1728 s | 1610 vs | 1340 vs | 270 | 544 w | 432 m | 632 m |
br: broad, vs: very sharp, v: sharp, m: medium, and w: weak.