A. M. Van Leusen

CHEMISTRY OF SULFONYLMETHYL ISOCYANIDES .21. USE OF DILITHIO-TOSYLMETHYL ISOCYANIDE IN THE SYNTHESIS OF OXAZOLES AND IMIDAZOLES

Abstract Dilithio-tosylmethyl isocyanide ( 2 ) reacts with the carbonyl of unsaturated esters to form oxazoles, unlike tosylmethyl isocyano monoanion which gives pyrroles by reaction with the conjugated carbon-carbon double bonds. Reaction of 2 with carbon-nitrogen multiple bonds leads to imidazoles, an example of which is the one-step synthesis of imidazo[5,1-a]isoquinoline from isoquinoline. From 2 and pyridine-N-oxide or pyridazine-N-oxide unsaturated ring opened products are obtained.

Formation and reactions of 2,3-dimethylene-2,3-dihydrothiophene

Abstract 2,3-Dimethylene-2,3-dihydrothiophene (the analogue of o-xylylene) is generated in situ from 3-(trimethylanunoniuinmethyl)-2-(trimethylsilylmethyl) thiophene iodide (7) by a fluoride induced 1,4-elimination process, and is identified by several [4+2] cycloadducts obtained in high yields.

A Simple One-Step Synthesis of 2-Cyanoadamantane, a Precursor to Adamantane-2-Carboxylic Acid

Abstract Quite recently 2-cyanoadamantane was prepared by Stetter and Tillmans2 in a three-step synthesis, starting from adamantanone. The overall yield was 56%. By hydrolysis of this cyanoadamantane a new and profitable synthetic route to adamantane-2-carboxylic acid was opened.2

CHEMISTRY OF ALPHA DIAZOSULFONES .14. SYNTHESIS OF ALPHA-ARYLSULFONYLPHENYLDIAZOMETHANES AND ALPHA-ALKYLSULFONYLPHENYLDIAZOMETHANES

Abstract Three general methods have been developed for the synthesis of α-diazosulfones, with special emphasis on the preparation of α-aryl substituted α-diazosulfones.

A new synthesis of α,β-unsaturated ketones. Allylic alkylation of 1-isocyano-1-tosylalkenes☆

Abstract Ketone (1) are homologated to enones 2 by alkylating (introduction of R 3 ) the condensation products 4 (derived from 1 and tosylmethyl isocyanide), followed by acid catalyzed hydrolysis.

Synthesis of N-(dimethylsulfamoyl)aldimines, a new type of aldimine derivative

Abstract N-(Dimethylsulfamoyl)aldimines (3) a new type of shelf-stable aldimine derivatives, are readily prepared from aldehydes and N-(dimethylsulfamoyl)amide (2) in refluxing toluene.

Improved Synthesis of 2,6,6-trimethyl-1-cyclohexene-1-acetaldehyde, a Key Intermediate for Drimane-related Sesquiterpenes.

Abstract The titel compound is conveniently prepared in 65% overall yield by a two step synthesis starting from the commercially available β-ionone.

AN IMPROVED SYNTHESIS OF TRIMETHYLSILYLMETHYL ISOCYANIDE

Abstract Trimethylsilylmethyl isocyanide is prepared by a new method which gives a higher overall yield and circumvents the use of methyl isocyanide.

SYNTHESIS OF SULFINYL CYANIDES

Abstract m-Chloroperbenzoic acid oxidation of thiocyanates provides a synthetic route to sulfinyl cyanides (2). 1-Adamantane-sulfinyl cyanide (2c) is prepared more efficiently from the corresponding sulfinyl chloride and sodium cyanide.

Synthesis of C-Sulfonylcarbohydroximoyl Chlorides from α-Diazosulfones and Nitrosyl Chloride1

Abstract Previous investigations in this laboratory have been concerned with reactions of α-diazosulfones2 (1) with electrophilic reagents, such as sulfenyl chlorides2, t-butyl hypochlorite2,3 and halogens4, which lead to threefold electronegatively substituted methanes (2). As was anticipated, α-diazosulfones closely resemble α-diazoketones in these reactions.5