Macrocycles rhomboid

High-yield preparation and characterization (multinuclear NMR, MS) of iodonium-containing macrocycles such as rhomboid [Eq. (4.113)], square, and... 

Stang and coworkers found that the interaction of bis[4-(4 -pyridyl)phenyl]-A3-iodane 146 with cis-(Et3P)2Pd(OTi)2 in acetone at room temperature results in hybrid A3-iodane-Pd tetranuclear macrocyclic square 147 via self-assembly [Eq. (118)] [227]. Its X-ray structure shows a planar rhomboid-like geometry rather than a perfect square. 

However, the nuclearity is not affected. Figure 44 shows the 2D network of [Cu2I2 i.-L30 2] 30, in which the adjacent rhomboid Cu(p,-I)2Cu units (d Cu-Cu 3.286 (4) A) are linked by one L30 ligand. The repeating 40-membered macrocycles of 30 are large enough to accommodate two free L30 molecules as guests in the cavities. 

The solid-state structure of (12) reveals that it consists of a planar, rhomboidal molecule with N-Pd-N angle of 84° and a C-l-C comer angle of 99°. Bis-pyridine ligands can be varied in numerous ways to yield a variety of diverse stractures these include macrocycles containing bis-pyridine functionalized Ceo molecules (13) and the bis-pyridine incorporated porphyrin compound (14). ... 

The high yield macrocyclization of iodonium containing macrocycles with rhomboid, square, and pentagonal shapes has been reported for example, /jiodonium triflate 25 with the diaryliodonium trifluoroacetate 26 gave rise (70 %) to the desired molecular square 27 <03JOC9209>. 

The formation of cationic iodonium macrocycles such as rhomboids, squares, or pentagons can be carried out in high yields by reaction of hypervalent iodoarenes with TMS-substituted aromatic compounds in the presence of TMSOTf (eq 106). ... 

The dimensions of the rhomboid macrocycle 42, which consists of two Pt(PEt3)2 units connected by two meta-carborane dicarboxylate dianions, were found to be 9.19 and 7.01 A, respectively (Das et al., 2005). 

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