Pentaprismane

Here are the strongest predicted peaks for prismane and pentaprismane ... 

The equally strained pentaprismanecarboxylic acid 7 was synthesized from 1-mesyloxy- or, even better, the 1-tosyloxyhomoprismanone, in which the mesyloxy and tosyloxy functions are the leaving groups. The parent hydrocarbon pentaprismane (8) was synthesized in three steps from 7 in 42% overall yield.59... 

The pentaprismane skeleton of Snio(2,6-Et2C6H3)io is composed of five four-membered rings and two flve-membered rings, as shown in Fig. 14.7.3(k). The average Sn-Sn bond length is 285.6 pm. 

In their syntheses of trishomohypostrophene 10a, trishomo-pentaprismane 11a, and the corresponding ketones 10b and lib... 

Figure 3-21. Polyhedral molecular models, (a) Tetrahedrane, (CH)4 (b) Tetra-tert-butyltetrahedrane, C[C(CH3)3] 4 [48] (c) Cubane, (CH)S (d) Dodecahedrane, (CH)2o (e) CeoHgo (f) Triprismane, C6H6 pentaprismane, CioHi0 and hexapris-mane, Ci2H12.

The Baeyer-Villiger oxidation has been utilized as an element of several novel functional group manipulations. Suginome and Yamada converted adamantanone (64) to 2-thiaadamantane (66) via the lactone (65 Scheme 19). Eaton et al.P in the synthesis of pentaprismane (70) from homopentaprismanone (67 Scheme 20), required that a leaving groiq) be introduced a to the carbonyl group in or r to carry out a Favorskii ring contraction. Oxidation of (67) afforded lactone (68), which was converted in several steps to the requisite hydroxy ketone (69). 

The Favorskii rearrangment was also successfully used as the key step in the synthesis of pentaprismane 359, and numerous other cases. 

Photodimerization of the dihydronicotinamide (101) yields the cis,syn,-cis-dimer (102). Subsequent irradiation of this yields the cage compound (103). Cage compound formation has also been reported as result of the photochemical ring closure of the adduct (104) this reaction proceeds efficiently to yield (105), which was used as a key intermediate in the synthesis of pentaprismane (106), The cage compounds (107) have been synthesized by... 

Diazabicyclo[2.2.2]oct-2-enes have been shown to undergo photoelimination of nitrogen in a similar fashion via singlet 1,4-biradicals.In a separate investigation, the azoalkane (32) was converted into the bicyclo[2.2.0]hexane (33) in 72% yield on irradiation, and an analogous transformation has been employed in the synthesis of compounds with a pentaprismane carbon skeleton. ... 

A classical method using Na- or Li-liquid ammonia (Birch reduction conditions) is effective for reductive dehalogenations of aryl and vinylic halides, but it is not always successfully applied to alkyl halides, although cyclopropyl halides and bridgehead halogens are exceptions.Under such conditions, the reactions are often accompanied by side reactions, such as elimination, the Wurtz coupling reaction, cyclization and reduction of carbonyl compounds. An example, a synthesis of pentaprismane (1), is shown in Scheme 4. ... 

Cage compounds have always been a subject of interest and fascination for chemists [2, 3]. The main reasons for this are probably the symmetry characteristics of esthetic molecules such as cubane (1) [4], prismane (2) [5], or pentaprismane (3) [6] (Scheme 6-1). In addition, the unusual reactivities of these polycyclic carbon systems have helped to promote the interest and actuality of such compounds over several decades. Finally, these unusual systems have often caused chemists to reconsider the conventional concepts of bonding in regard to atomic separations and bond angles and to develop new theories. 

Octabisvalene 74a and Cuneane 82 CioHio-saturated Cages Pentaprismane 10 and diademane 57 C,2H,2-saturated Cage Molecules Truncated Tetrahedrane 12, Hexaprismane 13, etc. 

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