Jia-Liang Zhu

A convenient new procedure for converting primary amides into nitriles

An operationally simple and high-yielding procedure has been developed for the conversion of primary amides to the corresponding nitriles, using ethyl dichlorophosphate/DBU as the mild dehydrating agent.

Lithium naphthalenide induced reductive alkylation of α-cyano ketones. A general method for regiocontrol of α, α-dialkylation of ketones

Abstract An efficient general method for the consecutive introduction of two alkyl groups to the α carbon of a ketone carbonyl has been developed, making use of the lithium naphthalenide induced reductive alkylation of an α-cyano ketone system as a key operation.

Bioactivity of 25-hydroxy-, 26-hydroxy, 25,26-dihydroxy- and 25,26-epoxybrassinolide

The bioactivity of 25-hydroxybrassinolide, (25S)- and (25R)-26-hydroxybrassinolide, (25S)- and (25R)-25,26-dihydroxybrassinolide, and of (25R)-25,26-epoxybrassinolide was tested in the rice leaf lamina inclination assay. The 25- and (25S)-26-hydroxy derivatives are known metabolites of the naturally-occurring phytohormone brassinolide, whereas the other compounds are novel, but closely related, congeners. When tested alone, all showed either no activity or only weak activity at relatively high doses. When coapplied with indole-3-acetic acid (IAA), an auxin that synergizes the effects of brassinosteroids, enhanced bioactivity was observed for each compound. However, even when applied together with IAA, none of the compounds proved more bioactive than brassinolide with or without IAA. We conclude from these results that enzymatic hydroxylation of endogenous brassinolide at C-25 and/or C-26 does not enhance brassinosteroid activity, and so does not comprise an activation pathway in brassinolide biosynthesis. Instead, these hydroxylations result in modest to appreciable metabolic deactivation.

Reductive alkylation of α-cyano ketones induced by samarium iodide

SmI2-HMPA was shown to be an effective reagent for reductive alkylation of α-cyano ketones, a useful process for regiocontrol of α,α-dialkylation of ketones.

A facile two-carbon ring expansion process based on the 2-cyano-1-vinylcycloalkanol system

Abstract Upon exposure to potassium hydride in THF in the presence of 18-crown-6, several 2-cyano-1-vinylcycloalkanol derivatives were found to undergo ring enlargement to give the corresponding γ-cyano cycloalkanones in synthetically useful yields.

Diels–Alder chemistry of 2-cyanoalk-2-enones. A convenient general approach to angularly substituted polycyclic systems

Under zinc chloride catalysis, a number of 2-cyanoalk-2-enones representing various ring sizes were found to undergo facile cycloaddition with several selected conjugated dienes; sequential treatment of the adducts with lithium naphthalenide and an alkylating agent resulted in the direct replacement of the angular cyano group with an alkyl group, providing easy access to angularly substituted polycyclic systems.