Intermolecular Coupling of Unsaturated Aldehydes and Ketones

Non-conjugated enones have also been coupled by low-valent titanium reagents, as illustrated by the synthesis of 14 [30]. The X-ray crystal structure of the racemic distellene 15 showed that the central C-C double bond is twisted by 10 and 14.5° for the two molecules in the unit cell [31]. Compound 16 should also be considered here since it permitted study of the electronic interaction between two [2.2]meta-cyclophane systems connected with a C=C bond [32], 

Product Tick Reducing Agent Soivent Yieid (%) Ref. 

3 Intermolecular Coupling of Aldehydes and Ketones with Functional Heteroatom Croups 

A series of dibromides including 19 served as monomers in the synthesis of poly(arylenevinylene)s, which exhibit high luminescence quantum yields [36], 

ESR and ENDOR investigations on the radical cation and radical anion of 27, the most expanded fulvalene reported to date, indicate that the free electron is delo- 

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