Titanium isopropoxide-mediated cis-selective synthesis of 3,4-substituted butyrolactones from CO2 was written by Sahari, Aleksi;Do, Cuong Dat;Mannisto, Jere K.;Antico, Emanuele;Amaratunga, Angelo;Hopmann, Kathrin H.;Repo, Timo. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2022.Name: 1-Bromo-4-methoxybutane This article mentions the following:
A Ti(OiPr)4-mediated multicomponent reaction, which produced 3,4-substituted cis-δ-lactones from alkyl magnesium chloride, benzaldehyde and CO2 was reported. The key intermediate, titanacyclopropane, was formed in-situ from Ti(OiPr)4 and a Grignard reagent, which enabled 1,2-dinucleophilic reactivity that is used to insert carbon dioxide and an aldehyde. An alternative reaction route was also described where a primary alkene was used to create the titanacyclopropane. A computational anal. of the elementary steps showed that the carbon dioxide and the aldehyde insertion proceeded through an inner-sphere mechanism. A variety of cis-butyrolactones were synthesized with up to 7 : 1 diastereoselectivity and 77% yield. In the experiment, the researchers used many compounds, for example, 1-Bromo-4-methoxybutane (cas: 4457-67-4Name: 1-Bromo-4-methoxybutane).
1-Bromo-4-methoxybutane (cas: 4457-67-4) belongs to organobromine compounds. Many of the organo bromine compounds are relatively nonpolar. Bromine is more electronegative than carbon (2.8 vs 2.5) and hence the carbon in a carbonbromine bond is electrophilic in nature. When the molecular ion is detected, the bromine and chlorine isotope patterns are very distinct, but caution is to be exercised for certain mixed chlorinated/brominated compounds, which can look similar to homohalogen patterns.Name: 1-Bromo-4-methoxybutane
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary