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The substrate-controlled diastereoselective arylation of chiral aldehydes readily available from carbohydrates is described, using the boron–zinc exchange reaction to generate the transferable aryl groups. The methodology developed was applied to the total synthesis of the styryllactone (+)-7-epi-goniofufurone and analogues thereof.

In this work we performed studies on the antimicrobial activities of α-phenylseleno citronellal and α-phenylseleno citronellol, two new selenium-containing citronella oil derivatives. The presence of phenylselenium group in the citronellal molecule increased antimicrobial activity, as compared to a natural, unsubstituted terpene. We assessed the antimicrobial activity of each compound against three important species of foodborne pathogenic bacteria: Listeria monocytogenes, Staphylococcus aureus and Salmonella Typhimurium, using the agar diffusion method and by measuring the minimum inhibitory concentration, all the tested compounds showed antimicrobial activity against the three bacteria used. The modified aldehyde showed good values of a minimum inhibitory concentration of 0.03 mM and antimicrobial activity against Salmonella Typhimurium at 6.400 arbitrary units per milliliter (AU/mL). The identification of the antimicrobial properties of compounds derived from citronella suggests that the use of these substances to protect food against pathogenic bacteria deserves further exploration.

PEG-400 and glycerin were successfully used as recyclable solvents for the synthesis of several alkenyl selenides and tellurides, in good yields and with high selectivity by the hydrochalcogenation of terminal alkynes. The nucleophilic species of selenium and tellurium were generated in situ from the reaction of the respective diphenyl dichalcogenide with NaBH4 at 60 °C. This easy, general and improved method furnishes the corresponding alkenyl chalcogenides preferentially with Z configuration. The PEG-400 can be reused up to 4 times without previous treatment with comparable yields and selectivity.

2-Phenylseleno aldehydes and ketones were selectively obtained using solid-supported catalyst (KF/Al2O3) and PEG-400 as clean, recyclable medium in good to excellent yields. The method was applied in the preparation of highly functionalized 2-phenylseleno citronellal and citronellol, potential bactericide agents. The catalytic system KF/Al2O3 and PEG-400 can be re-used for four times without previous treatment.

Mixed organozinc reagents have played an important role, especially because of its low reactivity, which makes them suitable for the use in asymmetric catalysis. 2 Considering our interest on the use of carbohydrates of as starting material for the synthesis of chiral molecules, and the peculiar reactivity pattern of organozinc reagents, particularly of type Zn-alkynyl-Alkyl and Zn-Aryl-Alkyl, in this report we present: The preparation of optically active secondary alcohols from diastereoselective addition of organozinc reagents to aldehydes obtained from sugars (D-mannitol, D-ribose and D-glucose).

Alumina-supported KF-promoted hydrothiolation of 1,3-butadiynes in PEG-400 or glycerol efficiently affords thiobutenynes with clear to complete (Z)-selectivity.

2-Phenylseleno aldehydes and ketones were selectively obtained using solid-supported catalyst (KF/Al2O3) and PEG-400 as clean, recyclable medium in good to excellent yields. The method was applied in the preparation of highly functionalized 2-phenylseleno citronellal and citronellol, potential bactericide agents. The catalytic system KF/Al2O3 and PEG-400 can be re-used for four times without previous treatment.

We describe herein the use of glycerol as an efficient, safe and recyclable solvent in the one-pot hetero-Diels–Alder (HDA) reaction of ( R )-citronellal with substituted arylamines. The catalyst-free reactions proceed easily using glycerol at 90 °C and the corresponding octahydroacridines (OHAs) were obtained in good to excellent yields by simply decantation of products. After removing the products, glycerol was directly reused for further HDA reactions without lost of activity.

PEG-400 and glycerol were successfully used as recyclable solvents for the synthesis of several organylthioenynes in good to excellent yields and high selectivity using solid supported catalyst (KF/Al2O3). This easy, general and improved method furnishes the corresponding alkenyl sulfides preferentially with Z configuration. The catalytic system and the glycerol or PEG-400 can be reused up to three times without previous treatment with comparable activity.

A new, clean, and efficient protocol is described for the hydrothiolation of terminal alkynes promoted by KF/Al2O3, using glycerol as recyclable solvent. This improved method furnishes selectively the corresponding anti-Markovnikov vinyl sulfides in good to excellent yields starting from terminal alkynes and aliphatic or aromatic thiols. The irradiation with microwaves facilitated the procedure and accelerates the reaction. The catalytic system and the glycerol can be re-used up to four times without previous treatment, and with comparable activity.