Highly regioselective [3,3] rearrangement of aliphatic allyl vinyl ethers catalyzed by a metalloporphyrin complex, Cr(TPP)Cl

Electron‐deficient vanadium(IV) tetraphenylporphyrin: A new, highly efficient and reusable catalyst for chemoselective trimethylsilylation of alcohols and phenols with hexamethyldisilazane

“…Suda's group has reported the use of chromium and iron porphyrins in organic synthesis. They used Cr(tpp)Cl for regioselective [3,3] rearrangement of aliphatic allyl vinyl ethers and for Claisen rearrangement of simple aliphatic allyl vinyl ethers, Fe(tpp)OTf for rearrangement of α,β-epoxy ketones into 1,2-diketones and rearrangement of monoalkyl-substituted epoxides into aldehydes, and Cr(tpp)OTf for highly regio-and stereoselective rearrangement of epoxides to aldehydes. [1 -7] The protection of hydroxy compounds is of great importance during various transformations in a synthetic sequence, especially in the synthesis of fine chemicals and natural products.…”

“…One disadvantage of HMDS is its poor silylating power in the absence of a suitable catalyst, needing forceful conditions and long reaction times in many cases. [10] To solve this problem, a variety of catalysts, including (CH 3 ) 3 SiCl, [11] ZrCl 4 , [12] ZnCl 2 , [13] K-10 montmorillonite, [14] LiClO 4 , [15] H 3 PW 12 O 40 , [16] iodine, [17] InBr 3 , [18] zirconium sulfophenyl phosphonate, [19] CuSO 4 .5H 2 O, [20] sulfonic acid-functionalized nanoporous silica, [21] MgBr 2 ·OEt 2 , [22] LaCl 3 , [23] poly(N-bromobenzene-1,3-disulfonamide) and N,N,N ,Ntetrabromobenzene-1,3-disulfonamide, [24] Fe(TFA) 3 , [25] Fe 3 O 4 , [26] (n-Bu 4 N)Br, [27] trichloroisocyanuric acid (TCCA), [28] HClO 4 -SiO 2 , [29] Pd [30] and ZrO(OTf) 2 , [31] have been reported for trimethylsilylation of alcohols and phenols. Although these procedures provide an improvement, many of the catalysts or activators need long reaction times, drastic reaction conditions or tedious workups, or are moisture-sensitive or expensive.…”

Graphene oxide‐bound electron‐deficient tin(IV) porphyrin: a highly efficient and selective catalyst for trimethylsilylation of alcohols and phenols with hexamethyldisilazane

“…Suda's group has reported the use of chromium and iron porphyrins in organic synthesis. They used Cr(tpp)Cl for regioselective [3] rearrangement of aliphatic allyl vinyl ethers and for Claisen rearrangement of simple aliphatic allyl vinyl ethers, Fe(tpp)OTf for rearrangement of α,β‐epoxy ketones into 1,2‐diketones and Cr(tpp)OTf for highly regio‐ and stereoselective rearrangement of epoxides to aldehydes . Recently, we have reported the use of tin(IV)tetraphenylporphyrinato perchlorate, tin(IV)tetraphenylporphyrinato trifluoromethanesulfonate, tin(IV)tetraphenylporphyrinato tetrafluoroborate and V(IV)tetraphenylporphyrinato trifluoromethanesulfonate in the ring opening of epoxides, protection of alcohols and phenols, fixation of CO 2 , olefination of aldehydes and cyclopropanation of olefins …”

“…They used Cr(tpp)Cl for regioselective [3] rearrangement of aliphatic allyl vinyl ethers and for Claisen rearrangement of simple aliphatic allyl vinyl ethers, Fe(tpp) OTf for rearrangement of α,β-epoxy ketones into 1,2diketones and Cr(tpp)OTf for highly regio-and stereoselective rearrangement of epoxides to aldehydes. [40][41][42][43] Recently, we have reported the use of tin(IV)tetraphenylporphyrinato perchlorate, tin(IV)tetraphenylporphyrinato trifluoromethanesulfonate, tin (IV)tetraphenylporphyrinato tetrafluoroborate and V(IV) tetraphenylporphyrinato trifluoromethanesulfonate in the ring opening of epoxides, protection of alcohols and phenols, fixation of CO 2 , olefination of aldehydes and cyclopropanation of olefins. [27][28][29][30][31][44][45][46][47][48][49][50][51][52][53][54][55] Graphene, a very recent rising star in materials science, with an atomically thin two-dimensional structure that consists of sp 2 -hybridized carbons, exhibits remarkable electronic and mechanical properties.…”

Highly efficient chemical fixation of carbon dioxide catalyzed by high-valent tetraphenylporphyrinatotin(IV) triflate

“…The Suda group has reported the use of chromium and iron porphyrins in organic synthesis. They used Cr (tpp)Cl for regioselective [3] rearrangement of aliphatic allyl vinyl ethers and for Claisen rearrangement of simple aliphatic allyl vinyl ethers, Fe(tpp)OTf for rearrangement of -epoxy ketones into 1,2-diketones and Cr(tpp)OTf for highly regio-and stereoselective rearrangement of epoxides to aldehydes [23][24][25].…”