Molecular belts. 2. Substrate-directed syntheses of belt-type and cage-type structures

Bioinspired Self‐Assembly I: Self‐Assembled Structures

“…42 For example, the interesting cage trinacrene 1 (Scheme 2.1), which was proposed as a suitable host for a range of organic, organometallic, and inorganic guests, 45 was prepared in a conventional four-step synthesis starting from furan and hexabromobenzene in an overall yield of less than 0.01%! 42,46 In view of the above propensity for conventional synthetic procedures to result in low overall yields, the use of a template strategy provides a potential means for assisting the formation of a particular cavity-containing product in higher yield. With regard to this, it is noted that templation is a common process employed by Nature for directing the formation of covalent bonds-as exemplified by the building of protein chains on messenger RNA via catalysis involving the ribosome.…”

Improved Synthesis of 1,2‐Bis(trimethylsilyl)benzenes using Rieke‐Magnesium or the Entrainment Method

“…Ref. [24] an issue (e.g., numerous applications of B; Scheme 1), the readily available 1,2-dibromo-4,5-dimethylbenzene [20] could be an economically attractive alternative to the parent 1,2-dibromobenzene as a starting material. Thus, we also investigated the reaction between Mg R /Mg e , Me 3 SiCl, and 1,2-dibromo-4,5-dimethylbenzene.…”

Reaction of 2,5-bis-trifluoromethyl-1,3,4-oxadiazole with 7-oxanorbornenes revisited: Experimental and quantum-chemical study of reaction stereoselectivity

“…Synthesis of the functionalized large hetero-bridged, synfacially fused norbornane ([n]polynorbornane) systems by employing Warrener's building BLOCK protocol [3] has a synthetic advantage over consecutive cycloaddition approaches used by Paddon-Row and co-workers [2b], Zimmt and co-workers [2c], Klä rner and co-workers [4], Stoddart and co-workers [5], and Lin and co-workers [6]. Using BLOCK protocol, the number of synthetic steps is significantly reduced and often higher yields of products result.…”

“…On the other hand, Warrener reported that syn-facial (exo,exo-) adducts 9 and 11 were prepared alongside anti-facial adducts 10 and 12 from 1,3,4-oxadiazoles 5 and 6, respectively, in which ester groups are substituted for one or both trifluoromethyl groups [3]. Furthermore, Warrener and Butler found that polycyclic bisoxygen bridged polarofacial substrate 13 by treatment with the 1,3,4-oxadiazole 1 produced exclusively bent-geometry of O 5 - [5]polynorbornane 14 (Scheme 2) [19].…”