Alternative General Synthetic Routes to [2.2]Cyclophanes and [3.2]Cyclophanes from [3.3]Cyclophane-2,11-diones by Photodecarbonylation, and a Structural Study of [3.2]Metacyclophanes

Abstract

Photodecarbonylation of [3.3]cyclophane-2,11-diones, which are readily prepared by TosMIC coupling, affords [2.2]cyclophanes in high yield. This method also provides a general synthetic method for [3.2]cyclophan-2-ones by taking advantage of the fact that this photochemical reaction proceeds in a stepwise manner through [3.2]cyclophan-2-ones. A series of [2.2]cyclophanes, [3.2]cyclophanes, and [3.3]cyclophanes can thus be made available from the common precursor [3.3]cyclophane-2,11-diones. In sharp contrast to the

Synthesis, Structure, and Transannular π−π Interaction of Multilayered [3.3]Metacyclophanes1

“…The central [3.3]MCP-dione unit takes the anti(twist boat/twist boat) conformation, where overlap of the benzene rings is increased as compared to that of the anti(chair/ chair) conformation of the parent 1 (Figure 5A). 24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å).…”

“…24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å). 17 Moreover, the transannular distance between C18 and C24 in the [3.3]MCP unit (4.363 Å) is much longer than that of 2 (4.171 Å).…”

“…16 As described previously, the assignment of an anti geometry to 1 is based on the highly shielded inner aromatic protons [Hi 1 δ 5.78 (br s)] from the outer aryl protons [Ha δ 7.19 (d) and Hb δ 7.32 (t)] due to the ring current effect of the facing benzene ring (Figure 3). 24 Two kinds of inner aromatic protons of the three-layered tetraone 29 [Hi 1 δ 6.09 (br s) and Hi 2 δ 5.54 (sharp s) (Figure S35)] are strongly shielded, while the outer aromatic protons appear in the normal aromatic region [Ha δ 7. 22 (dd) and Hb δ 7.37 (t)], suggesting the anti-anti geometry.…”

Synthesis, Structure, and Transannular π−π Interaction of Multilayered [3.3]Metacyclophanes1

“…The central [3.3]MCP-dione unit takes the anti(twist boat/twist boat) conformation, where overlap of the benzene rings is increased as compared to that of the anti(chair/ chair) conformation of the parent 1 (Figure 5A). 24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å).…”

“…24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å). 17 Moreover, the transannular distance between C18 and C24 in the [3.3]MCP unit (4.363 Å) is much longer than that of 2 (4.171 Å).…”

“…16 As described previously, the assignment of an anti geometry to 1 is based on the highly shielded inner aromatic protons [Hi 1 δ 5.78 (br s)] from the outer aryl protons [Ha δ 7.19 (d) and Hb δ 7.32 (t)] due to the ring current effect of the facing benzene ring (Figure 3). 24 Two kinds of inner aromatic protons of the three-layered tetraone 29 [Hi 1 δ 6.09 (br s) and Hi 2 δ 5.54 (sharp s) (Figure S35)] are strongly shielded, while the outer aromatic protons appear in the normal aromatic region [Ha δ 7. 22 (dd) and Hb δ 7.37 (t)], suggesting the anti-anti geometry.…”

Remarkable Solvatofluorochromism of a [2.2]Paracyclophane‐Containing Organoboron Complex: A Large Stokes Shift Promoted by Excited State Intramolecular Charge Transfer

“…Thus, derivatives of 2 BF 2 that have a broad response range which is similar to that of Reichardt's dye should be applicable as high‐performance polarity sensors. The development of novel luminescent materials which take advantage of the unique properties of π‐conjugated paracyclophane systems is currently under investigation.…”

Crystal structure of a four-layered [3.3](3,5)pyridinophane

“…However, the twist in the benzene rings in the central [3.3]MCP unit is quite large, at 11.6 between the C15-C18 and C28-C31 axes. The transannular distances between C8 and C18 [2.968 (3) Å ], C28 and C36 [2.955 (3) Å ], N1 and C15 [4.168 (3) Å ], and N2 and C31 [4.174 (3) Å ] are comparable to the distances in the parent two-layered [3.3]MCP (2.995 and 4.171 Å ) while the distance between C15 and C31 [2.910 (3) Å ] is much shorter than that in the parent two-layered [3.3]MCP-2,11-dione (2.99 Å ), which adopts an anti geometry (Isaji et al, 2001). The molecular structure of the title compound, showing the atomnumbering scheme.…”

Synthesis, Structure, and Transannular π−π Interaction of Multilayered [3.3]Metacyclophanes1

“…The central [3.3]MCP-dione unit takes the anti(twist boat/twist boat) conformation, where overlap of the benzene rings is increased as compared to that of the anti(chair/ chair) conformation of the parent 1 (Figure 5A). 24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å).…”

“…24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å). 17 Moreover, the transannular distance between C18 and C24 in the [3.3]MCP unit (4.363 Å) is much longer than that of 2 (4.171 Å).…”

“…16 As described previously, the assignment of an anti geometry to 1 is based on the highly shielded inner aromatic protons [Hi 1 δ 5.78 (br s)] from the outer aryl protons [Ha δ 7.19 (d) and Hb δ 7.32 (t)] due to the ring current effect of the facing benzene ring (Figure 3). 24 Two kinds of inner aromatic protons of the three-layered tetraone 29 [Hi 1 δ 6.09 (br s) and Hi 2 δ 5.54 (sharp s) (Figure S35)] are strongly shielded, while the outer aromatic protons appear in the normal aromatic region [Ha δ 7. 22 (dd) and Hb δ 7.37 (t)], suggesting the anti-anti geometry.…”

Remarkable Solvatofluorochromism of a [2.2]Paracyclophane‐Containing Organoboron Complex: A Large Stokes Shift Promoted by Excited State Intramolecular Charge Transfer

“…Thus, derivatives of 2 BF 2 that have a broad response range which is similar to that of Reichardt's dye should be applicable as high‐performance polarity sensors. The development of novel luminescent materials which take advantage of the unique properties of π‐conjugated paracyclophane systems is currently under investigation.…”

Crystal structure of a four-layered [3.3](3,5)pyridinophane

“…However, the twist in the benzene rings in the central [3.3]MCP unit is quite large, at 11.6 between the C15-C18 and C28-C31 axes. The transannular distances between C8 and C18 [2.968 (3) Å ], C28 and C36 [2.955 (3) Å ], N1 and C15 [4.168 (3) Å ], and N2 and C31 [4.174 (3) Å ] are comparable to the distances in the parent two-layered [3.3]MCP (2.995 and 4.171 Å ) while the distance between C15 and C31 [2.910 (3) Å ] is much shorter than that in the parent two-layered [3.3]MCP-2,11-dione (2.99 Å ), which adopts an anti geometry (Isaji et al, 2001). The molecular structure of the title compound, showing the atomnumbering scheme.…”

Synthesis, Structure, and Transannular π−π Interaction of Multilayered [3.3]Metacyclophanes1

“…The central [3.3]MCP-dione unit takes the anti(twist boat/twist boat) conformation, where overlap of the benzene rings is increased as compared to that of the anti(chair/ chair) conformation of the parent 1 (Figure 5A). 24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å).…”

“…24 Similar to the case of the three-layered MCP 3, the outer benzene rings are slightly distorted into the boat form [1.60°for C4-C5-C7-C8 and C5-C6-C7 planes and 4.61°for C4-C5-C7-C8 and C4-C9-C8 planes], whereas the inner benzene rings are distorted to the chair form [1.52°for C13-C14-C16-C17 and C13-C18-C17 planes and 2.56°for C13-C14-C16-C17 and C14-C15-C16 planes, respectively] in 23. 24 and 2 (2.995 Å). 17 Moreover, the transannular distance between C18 and C24 in the [3.3]MCP unit (4.363 Å) is much longer than that of 2 (4.171 Å).…”

“…16 As described previously, the assignment of an anti geometry to 1 is based on the highly shielded inner aromatic protons [Hi 1 δ 5.78 (br s)] from the outer aryl protons [Ha δ 7.19 (d) and Hb δ 7.32 (t)] due to the ring current effect of the facing benzene ring (Figure 3). 24 Two kinds of inner aromatic protons of the three-layered tetraone 29 [Hi 1 δ 6.09 (br s) and Hi 2 δ 5.54 (sharp s) (Figure S35)] are strongly shielded, while the outer aromatic protons appear in the normal aromatic region [Ha δ 7. 22 (dd) and Hb δ 7.37 (t)], suggesting the anti-anti geometry.…”

Remarkable Solvatofluorochromism of a [2.2]Paracyclophane‐Containing Organoboron Complex: A Large Stokes Shift Promoted by Excited State Intramolecular Charge Transfer

“…Thus, derivatives of 2 BF 2 that have a broad response range which is similar to that of Reichardt's dye should be applicable as high‐performance polarity sensors. The development of novel luminescent materials which take advantage of the unique properties of π‐conjugated paracyclophane systems is currently under investigation.…”

Crystal structure of a four-layered [3.3](3,5)pyridinophane

“…However, the twist in the benzene rings in the central [3.3]MCP unit is quite large, at 11.6 between the C15-C18 and C28-C31 axes. The transannular distances between C8 and C18 [2.968 (3) Å ], C28 and C36 [2.955 (3) Å ], N1 and C15 [4.168 (3) Å ], and N2 and C31 [4.174 (3) Å ] are comparable to the distances in the parent two-layered [3.3]MCP (2.995 and 4.171 Å ) while the distance between C15 and C31 [2.910 (3) Å ] is much shorter than that in the parent two-layered [3.3]MCP-2,11-dione (2.99 Å ), which adopts an anti geometry (Isaji et al, 2001). The molecular structure of the title compound, showing the atomnumbering scheme.…”