Sulfone Chemistry

In other work, sulfone chemistry plays an integral part of the syntheses of both -carotene and vitamin A by workers at Kuraray. In this approach, the anion of C q P-cyclogeranyl sulfone (36) is condensed with the C q aldehyde (37). The resulting P-hydroxy sulfone (38) is treated with dihydropyran followed by a double elimination to yield vitamin A acetate. Alternatively, the P-hydroxy sulfone (38) can be converted to the 5-halo sulfone (39) and a similar double elimination scheme is employed (23,24) (Fig. 8). 

Other approaches to direct C2Q couplings have been reported (9,30—35). Based on their knowledge of sulfone chemistry, Rhc ne-Poulenc has patented many syntheses of P-carotene which use this olefination chemistry (36—41). Homer-Emmons chemistry has also been employed for this purpose (42). The synthetic approaches to the carotenoids have been reviewed (43). 

The difference in sulfonation behavior between a-olefins (AO) and internal olefins (IO) has been a longstanding problem [14] and the literature is replete with earlier explanations [14,15] and practical solutions [16-20] to the problem of IO sulfonation. In their studies of IO sulfonation chemistry, Stapersma and colleagues [4], Radici et al. [21], Yoshimura et al. [22,23], and Roberts and Jackson [24] identified the origins of the poor sulfonatability of IO, and the process modifications required to produce good-quality IO sulfonate. 

Recent Developments in Sulfone Chemistry P. D. Magnus, Tetrahedron, 1977, 33, 2019-2045. 

In order to keep the chapter to a manageable size, rather strict definitions of what constitutes a halide and a transition metal have been chosen as a result, neither f-block chemistry nor organic sulfonate chemistry (with a few asides as exceptions) are included. 

The continuous development of the process design focused on appropriate snifonation equipment that is necessary to transfer all the findings from the parallel laboratory studies on the L AB-SO3 reaction kinetics and mechanisms to an industrial scale. Although these efforts have been initiated from the beginning of the use of synthetic surfactants, new doubts concerning sulfonation chemistry... 

Besides heterocyclic synthesis, the sulfone linker unit has also been applied to the preparation of a variety of other substrates. " " " " The diverse cleavage strategies that can be applied to cleave substrates from sulfone linkers make them a versatile multifunctional linker. This together with the simple purification process, compared to solution-phase synthesis, adds to the potential of sulfone chemistry being applied to solid-phase synthesis. 

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