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1(3H)-Isobenzofuranone (phthalides) and its derivatives possess a wide range of biological activities. A new method was found for the synthesis of 3-substituted phthalides featured with the convenient condensation reaction of 3-ethoxyphthalide with carbanions in high yields.

Transformations of 2-formylbenzoic acid provide direct access to a series of heterocyclic organic compounds such as phthalides and isoindolinones. Here, we use (+)-cinchonine as a catalyst in conjunction with nonafluoro-tert-butanol as a hydrogen-bond donor to afford enantiomerically enriched acylated 3-hydroxyphthalides with up to 99% yield and 90% ee through dynamic kinetic resolution. Moreover, various 3-alkoxyphthalides as well as 2-alkyl-3-hydroxy-1-isoindolinones were synthesized from 2-formylbenzoic acid.

For the preparation of 3-alkoxyphthalides from phthalaldehydes and alcohols, a cyclization reaction in the presence of a rhodium(III) catalyst and copper(II) salt is reported. Cyclization of phthalaldehydes also occurs with 1,3-dicarbonyl compounds under similar conditions to produce 3-substituted phthalides in good yields. An acylrhodium(III) species might be a key intermediate in these cyclization reactions.

Transition metal-catalyzed addition of arylboronic acids to 2-formylbenzoates afforded 3-substituted phthalides. By using SPINOL-based phosphites as ligands, a Rh(i)-catalyzed asymmetric version of such an addition reaction was achieved. The Royal Society of Chemistry 2010.

The configuration of concentricolide was assigned as (S). The configuration of its three analogs, which have anti-HIV-1 activity, were predicted by optical rotation values obtained by the B3LYP/aug-cc-pVDZ//B3LYP/6-31+G(d) and B3LYP/ aug-cc-pVDZ//MP2/6-31

Straightforward routes to fused tetrahydroindolizinones by two routes A and B, starting either from. 2-formylbenzoic acid and esters or from, β-hydroxy lactones via acyl iminium ions, are described. A plausible mechanism and limitations are given. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009.

β-Bromovinyl aldehydes reacts with carbon monoxide and alcohols at 125 °C in the presence of a catalytic amount of a palladium catalyst along with a base to give the corresponding carbonylative cyclized alkyl 2,5-dihydro-5-oxofuran-2-carboxylates in good yields. A reaction pathway involving intramolecular addition of acylpalladium to formyl group is proposed as a key step of this catalytic process.

Starting from Merrifield resin, 2-formylbenzoic acids were immobilized on solid supports. Reactions between immobilized 2-formylbenzoic acids and different organometallic reagents (Grignard reagents, zinc reagents, allyl silanes via Sakurai type reactions) furnished secondary alcohols which cyclized depending on the metal counter ion and reaction conditions, forming benzoannelated lactones. Asymmetric synthesis was possible on the resin using chiral [2.2]paracyclophane ligands. While the reaction of immobilized ortho-carboxy benzaldehydes with primary amines at elevated temperatures yielded 3-hydroxyisoindolinones, a reaction at ambient temperature allowed imine formation, which underwent 1,2-addition-cleavage reaction with various nucleophiles, yielding isoindolinones with three points of diversity.

2-Bromobenzaldehyde is carbonylatively cyclised with alcohols in the presence of a catalytic amount of PdCl2(PPh3)2/PPh3 together with a base to afford the corresponding 3-alkoxy-3H-isobenzofuran-1-ones in good

Irradiation of indane-1,2,3-trione in degassed alcoholic solutions affords 3-alkoxycarbonylphthalides as the major product together with 3-alkoxyphthalides. 3-Alkoxycarbonylphthalides may be derived from the reaction between alcohols and the spirooxiranone intermediate, generated photochemically by cleavage of the bond between two carbonyl groups of indane-1,2,3-trione via a cyclobutenone biradical derivative.

The palladium catalyzed carbonylative cyclization of o-bromobenzaldehyde 1 in alcoholic solution gave 3-alkoxyphthalides 3a-e in 61-85percent isolated yields via intramolecular cyclization induced by the coordinated formyl group on the palladium.

The photochemistry of benzocyclobutenedione in solution has been examined by use of laser flash photolysis techniques. Two rapid processes appear to compete. One leads to the formation of the long-lived bisketene IV, which can be readily observed (λmax 380 nm). The other process leads to oxacarbene III. This carbene could not be monitored directly, but probing techniques, with pyridine and adamantanethione as probes, lead to readily detectable ylides that can be employed to characterize the kinetic behavior of III. Thus, III lives about 20 μs in toluene and can be trapped by typical carbene scavengers such as alcohols. Carbene trapping by alcohols is in fact a complex reaction, since it also leads to equilibration with a short-lived intermediate (studied in detail in methanol/acetonitrile) that in turn can be trapped by alcohols, azides, and halides. This intermediate is tentatively assigned to carbocation VIII formed by solvent protonation of III.