Phthalides synthesis

Sakamoto, M., Sekine, N., Miyoshi, H., and Fujita, T. (2000) Absolute asymmetric phthalide synthesis via the solid-state photoreaction of AW-disubstituted 2-benzoylbenzamides involving a radical pair intermediate, J. Am. Chem. Soc., 122, 10210-10211. 

Scheme 24 Absolute asymmetric phthalide synthesis via aryl migration.

TTie lithiation of a l,6-methano[10]annulenamide occurs selectively at the peri position, but the lithiation of fused ring aromatics t es place preferentially at the ortho (rather than peri) position,as shown by the examples in Scheme 12. Subsequent transformations of the phthalides obtained in the naphthalene example also illustrate the usefulness of this method for the annelation of aromatic rings. The preference for ortho over peri lithiation holds true for phenanthrenes as well. The selective metd-ation of trimethoxyphenanthrenamide (15) followed by phthalide synthesis as above constitute the key steps in the synthesis of the phenanthroquinolizidine alkaloid cryptopleurine and the phenanthroindoli-zidine alkaloid antofme (Scheme 13). ... 

Methoxy phthalide could be synthesised by the usual method of phthalide synthesis, involving hydroxymethylation of /weM-methoxy benzoic acid. The orientation of... 

Carbonylation procedures were explored and applied in phthalide synthesis as well. In 1986, Negishi and co-workers studied the palladium-catalyzed cyclization of o-iodoatyl alkenyl ketones. By using Pd(dba)2 as the catalyst, bicyclic and polycyclic quinones could be produced in high yields. Interestingly, phthalides were formed when using Pd(OAc)2/PPh3 as the catalyst system (Scheme 2.159). Afterwards, the group carried out systematic studies on this topic. Lactones and lactams were produced selectively from various substrates. 

Lactones General Synthesis Synthesis of P-Lactones Synthesis of Butyrolactones Synthesis of Butenolides Synthesis of Phthalides Synthesis of Tetronic Acids Synthesis of a-Methylenebutyrolactones Synthesis of Valerolactones... 

Stoltz et al. [42] reported a phthalide synthesis from o-alkenylbenzoic acid 62 through oxidative cyclization using Pd(OCOCF3)2 catalyst xmder O2 atmosphere (Scheme 28). Ma and Yu also reported a synthesis of Y-methylene-y-butenohde 64 via Pd-catalyzed cyclization of 3,4-dienoic acid 63 in the presence of CUCI2 and K2CO3 [43]. 

Isobenzofuranone — see Phthalides, 552 Isobenzopyrylium salts isocoumarin synthesis from, 3, 834 synthesis, 3, 862, 863, 867, 868 Isobenzopyrylium salts, l-amino-3-aryl-synthesis, 3, 867 Isobenzopyrylium salts, 1-aryl-NMR, 3, 592... 

Phthalides — see Benzo[c]furan-l (3H)-one Phthalimide, 2-amino-pyridazine synthesis from, 3, 53 Phthalimide, N-cyclohexylthio-as vulcanization accelerator, 1, 404 Phthalimide. methylidine-polymerization, 1, 273 Phthalimide, N-(trichloromethylthio)-biocide, 1, 399 Phthalimide, 1-vinyl-polymerization, 1, 273 Phthalimide, N-vinyl-copolymer... 

The addition products were used for the total synthesis of racemic aporphine, protoberine, quettamin, and phthalide alkaloids26,24. 

The sequence was successfully applied to the synthesis of the phthalide isoquinoline hemiacetals (-)-egenine (6) and (-)-corytensine (7) from the bis-oxygenated precursor 513,14. 

Synthesis and Properties of Phthalide-Type Color Formers... 

Since the introduction of carbonless copying papers, CVL has undoubtedly found the most widespread use as a phthalide color former. Hence, it is appropriate to describe in detail the various approaches to its synthesis, particularly as they are representative of the preparations of various other phthalides described herein. 

Phthalic anhydride condenses with the aniline derivative in the presence of zinc or aluminum chlorides to yield the intermediate benzoyl-benzoic acid, which subsequently reacts with l,3-bis-V,V-dimethylaniline in acetic anhydride to yield the phthalide. The above compound gives a violet-gray image when applied to a clay developer. Clearly this synthesis is also very flexible and variations in shades of color formers have been obtained by varying the aniline components and also by using phthalic anhydrides substituted, for example, by nitro groups or chlorine atoms. Such products have excellent properties as color formers and have been used commercially. Furthermore, this synthetic route is of great importance for the preparation of heterocyclic substituted phthalides, as will be seen later. 

A wide variety of M W-assisted aldol [59, 60] and Knoevenagel condensation reactions have been accomplished using relatively benign reagents such as ammonium acetate [61], including the Gabriel synthesis of phthalides with potassium acetate [62],... 

The original synthesis of 206 was performed by heating pyrroles with phthaiic anhydride and acetic acid in a sealed tube. Oddo and co-workers prepared pyrrolene-phthalides in various ways from pyrrolylmagnes-ium bromides and phthaiic anhydride or 3,3-dichlorophthalide (23G265 25G235 34G289, 34G714). 

Benzo[c]furans (isobenzofurans) are reactive molecules usually employed as reactive dienes in the synthesis of more complex molecules. In the synthesis of spiro compounds related to fredericamycin A, Kumar generated the trimethylsiloxytrimethylsilylbenzo[c]furan 125 from phthalide via two consecutive deprotonations and silylations of the resulting anions. Diels-Alder reaction of the isobenzofuran as shown below with a spiroenedione leads to the formation of an endo-exo mixtures that can be smoothly converted to the dihydroxydione <00IJC(B)738>. 

Paint technologies, 18 54-55, 56 Paint viscosity, measuring, 18 69 Paired comparison test, 11 512 Paired synthesis, of phthalide and 4.4-butylbenzaldehyde, 9 680-681 PAI resins, properties of, 10 215t Pair production process, 21 313 Palatinit, 12 44... 

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