Table 3.
Selected bond lengths and angles of compounds 1a–3a, 1b–3b, 3c, and related literature data.[a]
| HC≡CR | M(C≡ CR)n | CN | M–C [Å] | C-M-C [°] | M-C≡C [°] | C≡C [Å] | Ref. |
|---|---|---|---|---|---|---|---|
| R=SiPh3 | [MgR2(thf)4] | 6 | 2.237(5)t | 180.0 | 173.2(8) | 1.226(2) | [17] |
| R=SiPh3 | [MgR2(tmeda)2] | 6 | 2.214(4)t | 180.0 | 173.9(4) | 1.221(5) | [17] |
| R=SiPh3 | 1a | 8 | 2.523(7)t | 168.7(2) | 162.4(5) | 1.229(8) | [14] |
| 2.558(7)t | 164.0(5) | 1.234(8) | |||||
| R=SiPh3 | 2a | 8 | 2.692(4)t | 166.0(1) | 158.9(9) | 1.201(5) | [14] |
| 2.723(4)t | 159.7(3) | ||||||
| R=SiPh3 | 3a | 8 | 2.785(2)t | 162.7(3) | 126.6(3) | 1.223(4) | [14] |
| 2.789(2)t | 141.3(3) | 1.236(5) | |||||
| R=4-t BuC6H4 | [MgR2([15]crown-5)] | 7 | 2.222(4)avt | 174.1(7) | 172.6(9) | 1.220(1) | [17] |
| 164.4(1) | |||||||
| R=4-t BuC6H4 | 1b[b] | 8 | molecule 1 | [16] | |||
| 2.512(1)t | 173.1(7) | 164.2(3) | 1.219(2) | ||||
| 2.512(1)t | 169.3(3) | 167.9(3) | 1.219(2) | ||||
| molecule 2 | |||||||
| 2.478(3)t | 154.4(7) | 160.2(3) | 1.219(2) | ||||
| 2.534(3)t | 161.8(7) | 174.4(3) | 1.219(2) | ||||
| molecule 3 | |||||||
| 2.536(3)t | 178.2(3) | 1.219(2) | |||||
| 2.561(3)t | 170.3(3) | 1.220(2) | |||||
| molecule 4 | |||||||
| 2.557(3)t | 165.8(3) | 1.219(2) | |||||
| 2.539(3)t | 173.5(3) | 1.219(2) | |||||
| R=4-tBuC6H4 | 2b | 8 | 2.693(4)t | 180.0 | 166.4(2) | 1.194(6) | [15,16] |
| 2.707(5)t | 180.0 | 167.0(4) | 1.196(6) | ||||
| R=4-tBuC6H4 | 3b[c] | 8 | molecule 1 | [15,16] | |||
| 2.95(3)t | 180.0 | 119(2) | 1.183(1) | ||||
| 2.80(3)t | 172.8(9) | 128(2) | 1.183(1) | ||||
| 2.72(4)t | 173.6(1) | 129(2) | 1.183(1) | ||||
| 174.1(1) | 134.0(2) | 1.183(1) | |||||
| molecule 2 | |||||||
| 2.78(4)t | 180.0 | 123(3) | 1.183(1) | ||||
| 2.77(3)t | 171.7(8) | 153(3) | 1.183(1) | ||||
| 3.01(2)t | 172.2(1) | ||||||
| 171.4(8) | |||||||
| R=tBu | [MgR2(tmeda)2] | 6 | 2.180(2)t | 180.0 | 176.0(2) | 1.216(3) | [17,35] |
| R=tBu | [Ca{(NDippCMe)2CH}(CCR)]2 | 4 | 2.496(2)br | – | 111.6(1) | 1.216(2) | [28] |
| 2.510(1)br | 157.9(9) | ||||||
| R=tBu | 3c | 8 | 2.847(1)t | 180.0 | 148.6(8) | 1.198(2) | [16] |
| R=C6H5 | [Mg(CCR)2(tmeda)2] | 6 | 2.176(6)t | 180.0 | – | 1.219(8) | [36] |
| 2.200(6)t | 1.213(8) | ||||||
| R=C6H5 | [Ca{(iPr)4C5H}(CCR)(thf)] | 7 | 2.551(8)br | – | 123.7(6) | 1.173(9) | [27] |
| 2.521(7)br | 141.7(6) | ||||||
| R=C6H5 | [Ca{(NDippCMe)2CH}(CCR)]2 | 4 | 2.505(2)br | – | 96.6(8) | 1.224(2) | [28] |
| 2.535(2)br | 172.8(5) | ||||||
| R=C6H4Me | [Ca{(NDippCMe)2CH}(CCR)]2 | 4 | 2.492(2)br | – | 94.5(3) | 1.221(2) | [28] |
| 2.530(2)br | 174.4(2) |
[a]
Dipp=2,6-iPr2(CH6H3); CN = coordination number; br = bridging, t = terminal, d = dimeric,
[b]
Four independent molecules.
[c]
Two independent molecules, both with disorder over three positions.